Fact-checked by Grok 2 weeks ago

PS

P.S. (or PS) is an abbreviation for postscriptum, a Latin term meaning "written after", used to denote an afterthought or supplementary remark appended to a letter, email, or other written message following the signature. Originating in handwritten correspondence as early as the , it allowed writers to include additional information without rewriting the main body, often for emphasis or forgotten details. Historical examples include its use by in a 1778 letter from West Point for emphatic punctuation. In modern usage, P.S. persists in digital communication to add concise notes, calls to , or personal touches that enhance engagement without disrupting the primary content, though overuse can dilute its impact. For further additions, P.P.S. (post postscriptum) extends the convention, reflecting the practical evolution from ink-and-paper constraints to electronic formats. This format underscores a causal link between pre-digital writing inefficiencies and the enduring need for structured addenda in concise .

Language and communication

Postscript

The abbreviation "PS" or "P.S." denotes postscriptum, a Latin term translating to "written after," referring to an appended to a following the main body and to include omitted details or afterthoughts. This practice originated in written correspondence, with the earliest recorded English usage of "postscript" appearing in 1551. The itself emerged in the 1610s as a for the full Latin phrase, facilitating concise notation in epistolary exchanges. Historically, postscripts served a practical function in pre-digital letter-writing by permitting writers to convey supplementary without necessitating a full redraft of the primary text, thus preserving the integrity of the initial composition while accommodating evolving thoughts or retrieved facts. This mechanism proved particularly valuable in eras when paper and ink were costly, and revisions cumbersome, enabling efficient augmentation of messages in business, personal, and official correspondence across from the onward. Empirical analysis of Renaissance-era letters reveals postscripts often reiterated key points for emphasis or added urgency, underscoring their role in enhancing communicative precision amid logistical constraints like unreliable delivery. In contemporary digital contexts, such as emails and text messages, PS retains its utility for appending non-essential yet relevant details, thereby maintaining the logical flow of the core message while signaling secondary content. Communication analyses indicate that PS sections in electronic formats can boost reader engagement by summarizing or teasing information, with one extended marketing experiment documenting up to 300% higher interaction rates for emails incorporating strategic PS lines compared to those without. This persistence reflects an underlying causal dynamic: PS structures information hierarchically, prioritizing primary intent while allowing undiluted inclusion of ancillary data, a pattern corroborated by preferences in reading behaviors where peripheral elements like PS are scanned for quick clarity.

Arts, entertainment, and media

Video games and computing entertainment

The (PS) brand denotes Sony Interactive Entertainment's flagship series of game consoles, which revolutionized consumer gaming hardware by prioritizing high-fidelity graphics and multimedia integration from inception. Launched in Japan on December 3, 1994, the original featured a custom-designed GPU capable of rendering up to 360,000 flat-shaded polygons per second, enabling developers to transition from sprites to fully realized polygonal environments and establishing Sony as a dominant force against incumbents like and . This hardware leap, combined with CD-ROM storage for larger game assets, sold tens of millions of units globally, fostering an ecosystem of third-party titles that emphasized immersive worlds over arcade-style gameplay. Subsequent generations built on this foundation, with the PlayStation 2 (PS2) debuting in 2000 as a DVD player hybrid that achieved unprecedented market penetration, while the PlayStation 3 (PS3) in 2006 introduced Blu-ray disc support and the Cell Broadband Engine processor for advanced parallel computing in physics simulations and HD rendering. The PS4 (2013) shifted to AMD x86 architecture for easier cross-platform development, and the PS5 (2020) incorporated a custom SSD with an integrated I/O complex, delivering compressed data throughput up to 9 GB/s—reducing load times in benchmarks from minutes on prior HDD-based systems to seconds, as demonstrated in tests transferring large assets like those in Cyberpunk 2077 in under 90 seconds. By mid-2025, PS5 hardware sales exceeded 80 million units worldwide, outpacing the PS3's lifetime U.S. installed base and underscoring sustained demand driven by empirical performance gains in ray-traced graphics and seamless open-world traversal. Despite these technical advancements, Sony's practices have drawn for prioritizing lock-in over user flexibility, including a 30% store cut that sparked U.S. class-action lawsuits alleging monopolistic pricing without competitive comparisons until recent updates, and regulatory sanctions in for abusing dominance in the PS4 digital marketplace by restricting third-party sales channels. The PS5's digital-only variant further exemplifies this trend, eliminating drives and compelling reliance on downloads prone to server dependencies, though Sony defends such shifts as enabling scalable updates and measures grounded in observed revenue data from digital sales outpacing . These tensions highlight a causal : hardware innovations democratizing access to photorealistic gaming for mass audiences, yet at the cost of reduced permanence compared to cartridge-era .

Music

"P.S. I Love You" is a written primarily by with contributions from , recorded by the English rock band . The track originated during the band's early songwriting efforts in 1962, featuring a bossa nova-influenced and lyrics depicting a writing to his from abroad, emphasizing themes of separation and affection through direct epistolary structure. The Beatles first attempted the song on 6 June 1962 at with drummer , but the version released stemmed from sessions on 4 September 1962, where 10 takes were recorded with on drums, followed by overdubs including McCartney's lead vocal and piano on 11 September. Released as the B-side to "" on 5 October 1962 by in the UK, the single reached number 17 on the Record Retailer chart, reflecting modest initial commercial success amid pay-for-play radio practices of the era. In the , issued it on 27 April 1964, where it peaked at number 10 on the for one week, buoyed by the Beatles' surging popularity post-Ed appearance. The song's production prioritized straightforward instrumentation—acoustic , drums, and minimalistic arrangement—recorded in mono to capture live-band energy, with sales exceeding 1.1 million copies worldwide by 1964 as part of the "" single's performance. Later included on the 1963 debut album , it demonstrated McCartney's melodic craftsmanship without reliance on orchestral embellishments, contrasting hype-driven narratives by grounding its appeal in empirical chart data and session logs rather than retrospective cultural elevation. P.S. Eliot was an American indie rock band formed in 2007 in , by twin sisters Katie and Allison Crutchfield, releasing three albums including Turbulent Times/Sad Songs (2008) and Saddle Creek (2011), characterized by raw energy and lo-fi production that influenced subsequent projects like . The band's output, limited to around 20 tracks across EPs and full-lengths, achieved niche recognition in underground circuits with print runs under 1,000 for early releases, prioritizing DIY ethos over mainstream metrics.

Literature

"PS, I Love You" is a by Irish author , first published on February 3, 2004, by . The narrative centers on Holly Kennedy, who receives monthly letters from her late husband Gerry, each beginning with directives and revelations intended to help her navigate life after his death from a at age 30. These posthumous communications, totaling ten letters delivered sequentially, employ an epistolary structure to reveal Gerry's pre-arranged guidance, mimicking additions that extend beyond the "signature" of his lifetime actions. The letters function as therapeutic interventions, prompting Holly to confront grief through specific tasks like skydiving or singing , thereby layering emotional disclosures after the main storyline of their . The novel achieved commercial success, selling over one million copies in the per Nielsen data and becoming a worldwide million-copy . Ahern, then 21 years old, drew from personal observations of loss to craft the premise, intending the letters to represent enduring spousal support amid tragedy. Another example is "P.S. Longer Letter Later," a young adult novel in letters co-authored by and , published in April 1998 by Scholastic Press. The story unfolds through correspondence between friends and , separated by family moves and personal challenges like and illness, with postscripts adding candid afterthoughts that deepen character insights and resolve subplots. This format echoes traditional epistolary techniques by using appended notes for unfiltered revelations, enhancing narrative intimacy without altering the primary exchange. "P.S.," a by Helen Schulman published on May 18, 2001, by Bloomsbury USA, explores themes of midlife reinvention and through Louise Harrington's encounters, incorporating postscript-like reflections in its stream-of-consciousness style to punctuate key emotional turns. Schulman's intent emphasized witty examinations of desire, with the title nodding to incidental addendums in personal correspondence.

Film, television, and stage

"P.S. I Love You" is a romantic drama film directed by , adapted from Cecelia Ahern's 2004 novel of the same name. The film stars as Holly Kennedy, a widow who receives posthumous letters from her late husband (played by ) guiding her through grief, with supporting roles by , , and . It premiered on December 21, , and earned $53.7 million at the domestic and $156.8 million worldwide. "P.S." (2004) is an drama film directed by Kidd, based on Schulman's 2001 novel. Starring as Louise Harrington, a Columbia University admissions officer who encounters a young applicant () resembling her deceased high school boyfriend, the film explores themes of second chances and unresolved pasts. It premiered at the on September 13, 2004, before a limited U.S. theatrical release, receiving mixed reviews for its introspective narrative but limited commercial data due to its status. "P.S. Your Cat Is Dead!" (2002) is an American comedy-drama film directed by and starring , adapted from 's 1972 novel and play. The story follows an out-of-work (Guttenberg) who discovers a burglar () in his apartment on and holds him hostage amid personal crises, including the titular postscript note about his cat's death. Released directly to video in some markets after a limited theatrical run, it garnered a 24% approval rating on based on 17 reviews, with critics noting its raunchy humor but uneven execution. "P.S. Your Cat Is Dead!" originated as a stage play by James Kirkwood Jr., first produced Off-Broadway in 1972 before transferring to Broadway's John Golden Theatre on April 7, 1975, where it ran for 145 performances. The comedy features a bisexual actor confronting loss, identity, and an intruding thief, with early casts including Keir Dullea and Tony Musante; it has seen regional revivals, including a 2013 Los Angeles production and a 2024 script-in-hand reading in London. The play's structure leverages postscript motifs for ironic revelations, emphasizing causal chains of misfortune over sentimentality in its farce elements. Television productions incorporating "P.S." are sparse, with "P.S. " (Post Seismic Life) serving as Nepal's first online , launched around 2016, depicting comedic and dramatic lives of youth post-earthquake through episodic postscripts to everyday chaos, though viewership metrics remain undocumented in major databases. No major broadcast network episodes or series prominently titled with "P.S." or postscript motifs have achieved significant empirical viewership records.

Other creative media

PS Magazine, subtitled The Preventive Maintenance Monthly, is a United States Army publication employing comic book illustrations to convey equipment maintenance and safety instructions to military personnel. Launched in June 1951 under the direction of comic artist Will Eisner, it originated from earlier World War II-era efforts like Army Motors to improve vehicle upkeep through accessible visuals rather than dense manuals. The series featured recurring characters such as Connie Rodd to simplify technical concepts, achieving broad internal distribution within the Army for practical training. By 2021, it marked 70 years of production, with over 775 issues released, though print editions ended in November 2019 amid a shift to digital formats. Its impact remained confined to military contexts, demonstrating comics' utility for instructional communication without broader commercial entertainment appeal.

Science and technology

Computing and software

(PS) is a device-independent and full programming language developed by Systems to describe the appearance of text, graphics, and images for output to printers and displays. It employs a stack-based architecture, enabling vector-based rendering of scalable fonts and shapes without reliance on specific resolutions. First commercially released in 1984 after development beginning in 1982, PostScript standardized high-fidelity by separating content description from rendering, allowing consistent results across diverse devices. The language evolved through defined levels to address performance and feature needs: Level 1 (1984) supported basic monochrome output and outline fonts; Level 2 (1990) introduced , , and resource reuse for faster processing; and Level 3 (1997) added advanced device controls, smoother gradients, and support for high-volume production printing. These enhancements maintained while improving efficiency, with empirical benchmarks showing Level 2 reducing file sizes by up to 50% via operators like LZW. PostScript's Turing-complete nature permits complex scripting, including loops and conditionals, beyond mere page markup. In software ecosystems, PostScript powered desktop publishing applications by integrating with tools like and Aldus PageMaker, where the 1985 Apple LaserWriter—featuring an embedded interpreter—enabled what-you-see-is-what-you-get () workflows on Macintosh systems, driving industry adoption with over 100,000 units sold by 1987. This causal linkage is evident in metrics: revenues grew from negligible in 1984 to $1.5 billion by 1990, attributable to PostScript's resolution-independent scaling that eliminated bitmap limitations of dot-matrix printers. Early macOS predecessors relied on for printer drivers, though later versions transitioned to native PDF rendering via in 2001 for reduced complexity. PostScript influenced PDF development, with Adobe's Acrobat Distiller (1993) converting PS files to the more structured Portable Document Format, which inherits PS's vector primitives but adds interactivity and compression for digital distribution. Proprietary aspects drew criticism for restricting interpreter modifications and , potentially inflating costs—e.g., licensing fees reached millions for printer manufacturers—yet verifiable persisted through Adobe's public specifications, enabling third-party implementations. , an open-source PostScript and PDF interpreter released in 1988, demonstrated compatibility by processing Level 3 files without Adobe binaries, supporting formats like EPS and fostering software like CUPS for Unix printing. Adobe partially addressed proprietary concerns in 2022 by open-sourcing PostScript Level 1 code via the , facilitating study of its 301,000-line implementation in Interpress-derived syntax. Despite biases in academic narratives favoring open formats, PostScript's empirical success—powering 90% of professional printing by the 1990s—stems from its robust error handling and mathematical precision in bezier curves, outweighing alternatives like PCL in vector fidelity.

Units of measurement

The (ps) denotes a in the (SI), defined as $10^{-12} seconds, equivalent to one trillionth of a second. This scale enables precise of ultrafast phenomena, particularly in physics and , where pulse durations on the order of picoseconds facilitate observation of atomic and . employed picosecond pulses in his foundational studies of chemical reaction transition states, laying the groundwork for and earning the Nobel Prize in Chemistry for advancing real-time observation of bond breaking and formation at these timescales. The picosiemens (pS) represents a derived unit of electrical conductance, equal to $10^{-12} , used to quantify minute conductivities in physical systems such as nanoscale electronic components and quantum transport experiments. In these contexts, pS measurements provide empirical data on charge flow under conditions of low resistance, as defined by the reciprocal of the in SI standards. The petasecond (Ps) signifies a unit of time equal to $10^{15} seconds, roughly 31.7 million years, applied in scientific assessments of extended temporal scales in geophysics and cosmology for modeling processes like tectonic shifts or stellar evolution durations.

Medicine and biology

In biology, PS denotes phosphatidylserine, an anionic phospholipid component of cell membranes, particularly enriched in the inner leaflet of the plasma membrane where it constitutes about 5-10% of total phospholipids. PS maintains membrane asymmetry through the action of ATP-dependent flippases, which translocate it inward, while scramblases enable bidirectional movement under specific conditions. During apoptosis, PS externalization to the outer leaflet serves as an "eat-me" signal for phagocytic clearance, a process first biochemically characterized in the early 1990s through studies demonstrating its exposure on apoptotic lymphocytes and subsequent recognition by macrophages. This exposure is mediated by calcium-dependent scramblases like TMEM16F and inhibited by flippases such as ATP11A/C, with dysregulation linked to impaired efferocytosis in conditions like systemic lupus erythematosus. In medical contexts, PS externalization extends beyond to processes like platelet activation and non-, where it facilitates or alternative clearance pathways, though its role in the latter remains under investigation via scramblase-independent mechanisms. Therapeutic interest in exogenous PS, often derived from soy or bovine sources, focuses on cognitive enhancement, with randomized controlled trials showing modest improvements in and attention in patients after 12 weeks of 100-300 mg daily supplementation. However, larger meta-analyses indicate inconsistent benefits for healthy adults or advanced , with effects potentially confounded by DHA co-supplementation and limited long-term data, underscoring the need for caution against unsubstantiated claims of broad neuroprotective efficacy. In cardiology, PS abbreviates pulmonary stenosis, a congenital valvular defect characterized by narrowing of the pulmonary valve or outflow tract, impeding right ventricular ejection to the pulmonary artery. It accounts for 7-12% of all congenital heart defects, with valvar PS being the most common subtype, often isolated but associated with syndromes like Noonan syndrome in 20-30% of cases. Severity varies: mild PS (gradient <40 mmHg) may remain asymptomatic into adulthood, while severe cases (gradient >64 mmHg) present in infancy with cyanosis, right ventricular hypertrophy, and heart failure, diagnosed via echocardiography showing dome-shaped valve morphology. Balloon valvuloplasty yields >80% success in reducing gradients below 30 mmHg for non-dysplastic valves, with surgical intervention reserved for dysplastic or residual severe stenosis. Long-term prognosis is excellent post-intervention, with <5% recurrence requiring re-intervention by age 20.

Physics and chemistry

In classical mechanics and statistical mechanics, PS denotes phase space, the configuration space extended by conjugate momenta, representing all possible states of a . For a system of N particles in three dimensions, is $6N-dimensional, with each point specifying positions \mathbf{q} and momenta \mathbf{p}. Trajectories in evolve deterministically under Hamilton's equations, \dot{q_i} = \frac{\partial H}{\partial p_i} and \dot{p_i} = -\frac{\partial H}{\partial q_i}, where H is the . This framework enables computation of statistical averages via , which preserves volume along flows, validated in simulations of ergodic systems like hard-sphere gases. The , central to applying in , asserts that time averages over a single equal ensemble averages over the invariant measure in , as formulated by Boltzmann in the late . Experimental support comes from long-time simulations and observations in isolated systems, such as ultracold gases, where deviations occur only under non-ergodic constraints like integrability. Non-empirical extensions, such as assuming without exploration, have been critiqued for overlooking KAM tori in nearly integrable systems, where foliates into invariant tori preserving variables. In quantum , PS refers to pseudospin, an emergent two-level degree of freedom mimicking but arising from structural symmetries, such as sublattice pseudospin in 's lattice. In , isolated in 2004 by Novoselov and Geim, low-energy electrons behave as massless Dirac fermions with pseudospin texture locked to , leading to Berry phase effects observable in cyclotron orbits. This was experimentally confirmed via quantum Hall measurements showing half-integer plateaus, deviating from integer values in conventional 2D systems, with conductance \sigma_{xy} = \pm 4(n + 1/2) \frac{e^2}{h} for filling factor n, as reported in 2005 transport experiments. Pseudospin-mediated phenomena, including Klein tunneling—perfect at incidence due to pseudospin —have been verified in graphene p-n junctions via , with transmission probabilities approaching 100% as predicted by the Dirac H = v_F \boldsymbol{\sigma} \cdot \mathbf{p}, where v_F is Fermi velocity and \boldsymbol{\sigma} Pauli matrices encode pseudospin. Valley-dependent pseudospin control enables pseudomagnetic fields up to 300 T in strained graphene, measured through Landau level in 2010 experiments, underpinning applications in without real magnetic fields. Interpretations relying solely on without momentum-resolved overlook intervalley , which mixes pseudospins but preserves overall conservation in defect-free samples.

Transportation

Vehicles and maritime

In , "PS" denotes , a hydraulic or electric system that assists the driver in turning the vehicle's wheels by reducing the physical effort required, particularly beneficial for larger or heavier automobiles. The concept was pioneered by American engineer Francis W. Davis, who developed and patented a hydraulic power steering mechanism in 1926 while working on heavy trucks for Pierce-Arrow, addressing the steering challenges posed by increasing vehicle sizes and engine power during the early . Commercial adoption accelerated in the post-World War II era, with introducing the first production car equipped with —the 1951 Imperial model—using a hydraulic system that applied engine-driven fluid pressure to amplify steering input. By the mid-1950s, became standard on many U.S. luxury and mid-range vehicles from manufacturers like and , driven by consumer demand for reduced driver fatigue on expanding highways and empirical tests showing up to 80% less steering effort compared to manual systems. This shift improved vehicle maneuverability, with engineering analyses indicating lower accident rates in low-speed scenarios due to enhanced control precision, though it initially added minor fuel consumption penalties from the hydraulic pump's on the engine. In maritime contexts, "PS" refers to paddle steamers, side- or stern-wheeled vessels propelled by steam engines driving large rotating paddles, which emerged as a pivotal technology during the in the early . The first commercially successful , Robert Fulton's Clermont, launched on the in 1807, demonstrated reliable upstream navigation against river currents, fundamentally altering inland and coastal transport by decoupling movement from wind dependency. proliferated on major trade arteries like the in the U.S. and the Murray-Darling system in , where by the they hauled bulk cargoes such as cotton, wool, and timber at speeds of 8-12 knots, reducing transit times from weeks to days and expanding market access for agricultural goods. Their causal role in trade expansion stemmed from steam power's ability to operate in shallow drafts and variable conditions unsuitable for ships, fostering in frontier regions; for instance, U.S. river traffic volume surged over 500% between 1820 and 1840, correlating with deployment and enabling reliable supply chains that supported industrialization. However, limitations like vulnerability to propeller-driven screw steamers after the 1840s—introduced for ocean voyages—led to their decline in deep-sea roles, confining later PS vessels to riverine and excursion services where paddle efficiency in shallows persisted until diesel alternatives dominated by the mid-20th century.

Places and geography

Settlements and regions

The code PS designates the , a partially recognized sovereign entity comprising the (including ) and the in Western Asia, with approximate central coordinates of 31°57′N 35°13′E. The region's population was estimated at 5,483,450 in mid-2023, reflecting dense urban centers like and amid ongoing territorial disputes and administrative divisions between the Palestinian Authority and governance. Historical records indicate continuous habitation since , with demographic shifts influenced by successive empires including , British Mandate, and post-1948 partitions. Psara (Ψαρά), a small island municipality in the Sea off , , lies at coordinates 38°33′N 25°34′E and covers 44.5 km². Its 2021 population stood at 458 residents, primarily in the main settlement of Psara town, down from a pre-19th-century peak exceeding 7,000 due to historical depopulation events. Etymologically linked to ancient references possibly meaning "spotted" or from Mycenaean-era settlements, the island's demographics derive from maritime communities; it resisted forces during the Greek War of Independence, culminating in the near-total destruction of its fortifications and population in a 1824 massacre that killed or enslaved thousands. Formerly, the FIPS 10-4 PS referred to , an archipelago in the western at roughly 7°30′N 134°30′E, with a 2023 population of 18,058 across 340 islands; this code preceded the current ISO assignment following U.S. administration until in 1994. 's settlements, concentrated in and , feature Micronesian demographics shaped by volcanic and geography, with historical influences from , , , and rule.

Organizations and politics

Political entities

The Parti Socialiste (PS), or Socialist Party, in emerged in 1969 from the Congress of , where the Section Française de l'Internationale Ouvrière (SFIO) and allied groups unified under leaders including to revitalize socialist politics amid electoral fragmentation. Its platform centered on social democratic principles, advocating state-led economic planning, wealth redistribution, and expanded welfare, drawing from Marxist influences but adapted to democratic frameworks. The PS achieved national governance following Mitterrand's 1981 presidential victory, forming coalitions that implemented nationalizations of 39 major firms and 11 banks by 1982, alongside hikes of 25% and a push for shorter workweeks. These policies aimed to stimulate demand and reduce but triggered , peaking at 14% in 1982, and a deficit surge to 3.5% of GDP. By 1983, mounting —rising from 7.4% in 1980 to 8.3%—and fiscal pressures forced the "tournant de la rigueur," shifting to spending cuts and tax hikes that aligned with constraints, stabilizing the but entrenching higher above 10% through the 1990s. Empirical assessments attribute limited GDP growth (averaging 1.8% annually 1981-1985) to rigid labor regulations and distorted incentives from , which empirical studies link to 10-15% productivity gaps in nationalized sectors versus private ones. Subsequent PS administrations, such as Lionel Jospin's 1997-2002 term, pursued moderated reforms including the , which correlated with modest employment gains but persistent fiscal deficits exceeding 3% of GDP and critiques of reduced competitiveness due to higher labor costs. results reflect declining support: the PS secured 29.4% in 1981 legislative votes but fell to 6.2% in the 2022 presidential first round, signaling voter shifts toward alternatives amid stagnant wages and debt-to-GDP ratios climbing to 112% by 2020. Statiste emphases in PS platforms have faced right-leaning economic critiques for causal links to inefficiency, as nationalized entities underinvested in capital (e.g., 20% lower R&D spending) and required bailouts totaling billions, contrasting with boosts from 1986-1993 privatizations. Beyond France, PS denotes the Polish Socialist Party (Polska Partia Socjalistyczna, ), founded in 1892 in amid , prioritizing independence through while rejecting Bolshevik centralism in favor of democratic federalism. Influential in the Second , it won 9.0% of seats in 1922 elections and supported land reforms, but communist suppression post-1945 dissolved it until refounding in 1989 as a democratic socialist entity opposing market shock therapy's social costs. Today marginal, it polled under 1% in 2019 parliamentary elections, with platforms critiqued for echoing statist inefficiencies seen in pre-1989 Poland, where centralized planning yielded GDP per capita 40% below Western Europe's by 1989 due to misallocated resources and stifling.

Religious and honorary groups

In and religious texts, "PS" or "Ps" serves as the standard abbreviation for the , a compilation of 150 ancient Hebrew poems, hymns, and prayers forming the third section of the in the and part of the in Christian canons. This convention, adopted in scholarly references like those from the Society of Biblical Literature, facilitates precise citation of individual psalms, such as Ps 23 ("The Lord is my shepherd"), which emphasizes themes of divine provision and trust rooted in pastoral imagery. The plural form "Pss" denotes multiple psalms, reflecting their collective liturgical use in Jewish services (as Tehillim) and Christian worship across Protestant, Catholic, and Orthodox traditions. Doctrinally, the Psalms underpin key theological concepts including lament, praise, and covenantal fidelity, with traditional attributions to figures like King David (for about half) supported by superscriptions, though modern textual analysis identifies diverse authorship spanning centuries from the monarchic period to post-exilic times. Empirical data from manuscript evidence, such as the Dead Sea Scrolls (dating to 150 BCE–70 CE), confirms the book's antiquity and stability, with over 30 partial scrolls attesting to its core content despite minor variants. In religious practice, adherence manifests in daily recitation mandates, like the Orthodox Church's use of kathismata divisions for monastic offices, prioritizing the texts' original poetic structure over later interpretive overlays. Numbering discrepancies arise from source traditions: the Masoretic Text (basis for most Protestant versions) separates Psalms 9 and 10 as distinct, while the Septuagint (influencing Catholic and Eastern Orthodox Bibles) combines them into one, shifting subsequent numbers by one until Psalm 147, then by two thereafter, totaling 151 in some Greek manuscripts due to an extra doxology. These variances, traceable to translational decisions around acrostic structures and thematic unity, necessitate caution in cross-denominational citations to avoid doctrinal misalignments, as seen in liturgical schisms where Hebrew primacy clashed with Septuagint authority during early church councils.

Miscellaneous uses

Abbreviations in economics and military

In economics, "PS" most commonly abbreviates producer surplus, defined as the difference between the a producer receives for a good or service and the minimum they would accept to supply it, graphically represented as the area above the supply curve and below the market equilibrium. This metric quantifies economic gains to sellers from , with empirical calculations often derived from supply-demand models; for instance, in U.S. agricultural markets, PS estimates from 2020-2023 averaged $15-20 billion annually for major crops like corn and soybeans, based on USDA and yield data integrated with econometric models. However, PS expansions via government interventions like supports—mechanisms setting floor prices above equilibrium to bolster farm incomes—have been critiqued for causal distortions: they incentivize , generating surpluses that require taxpayer-funded storage or purchases, with net social losses exceeding $10 billion yearly in the U.S. from 2010-2020 per cost-benefit analyses, as deadweight losses from reduced surplus outweigh PS gains. Studies of post-WWII U.S. policies under the Agricultural Adjustment Acts confirm this, showing farm output 20-30% above free-market levels due to supports, debunking myths of pure efficiency by revealing persistent inefficiencies like soil depletion and barriers, unsupported by randomized policy trials or long-term yield data. In military contexts, "PS" abbreviates Personnel Specialist in the U.S. , a responsible for administrative support including pay, personnel records, and for enlisted sailors, established under codes since the 1970s reorganization. PS personnel manage over 300,000 active-duty records annually, with declassified organizational charts from Navy directives (e.g., OPNAVINST 1220.1) detailing their integration into fleet support units, ensuring operational readiness through data-driven metrics like retention rates, which improved 5-7% post-2010 admin reforms. Alternatively, "PS" denotes Port Security in U.S. Army and joint operations, encompassing for harbors and waterfronts against , as codified in like FM 3-34.119 (Engineer Operations), with empirical evaluations from exercises showing vulnerability reductions of 40-50% via PS protocols, though cost-benefit ratios vary, with annual expenditures exceeding $500 million amid debates over efficacy against asymmetric threats absent comprehensive threat modeling. These uses highlight PS's role in causal chains of logistical efficiency, where lapses correlate with documented disruptions, such as 1991 port delays traced to inadequate PS staffing in after-action reports.

Other specialized terms

In British educational parlance, PS abbreviates , referring to a select group of independent, fee-paying institutions like and that originated in the 15th–19th centuries to educate the elite. These schools, distinct from state-funded comprehensives, emphasize classical curricula, extracurriculars, and networking, with annual fees at Eton reaching £52,749 for 2023–24 and projected to increase to about £63,000 from January 2025 due to new on private tuition. Data from the reveal that attendees, despite comprising 7% of the pupil population, hold 44% of top jobs, 43% of leading journalists, and 39% of top doctors as of recent analyses, correlating with higher intergenerational mobility for those admitted—often via scholarships covering up to 100% of costs for lower-income families—though access remains skewed toward higher socioeconomic brackets, with only 1–2% of places going to pupils annually. This pattern underscores the causal role of institutional prestige and connections in outcomes, countering assumptions of in meritocratic systems by highlighting selection effects and resource disparities. In and , PS stands for , a fragmenting data into discrete packets routed dynamically across networks to optimize , pioneered independently by in 1964 and in 1965. The technique formed the core of , launched October 29, 1969, by the U.S. Advanced Research Projects Agency as the first operational wide-area packet-switched network, transmitting initial messages between UCLA and Stanford Research Institute and laying groundwork for TCP/IP protocols adopted DoD-wide by 1983.