Pip
pip is a package-management system written in Python and distributed as a standalone tool, primarily used to install, upgrade, and manage software packages available from the Python Package Index (PyPI) and other repositories.[1][2] It resolves dependencies automatically, supports virtual environments, and has become the de facto standard for handling Python libraries, enabling developers to extend Python's functionality without manual compilation or distribution management. Originally created by Ian Bicking in 2008 as a more reliable alternative to earlier tools like easy_install, pip's name derives from the recursive acronym "Pip Installs Packages," and it was later maintained under the Python Packaging Authority (PyPA).[3] Since Python 3.4, released in 2014, pip has been bundled by default with official Python distributions, contributing to its widespread adoption across millions of users and the ecosystem's growth to over 500,000 packages on PyPI as of 2025.[4] While praised for simplifying package distribution, pip has faced critiques for occasional dependency resolution conflicts in complex projects, prompting innovations like improved resolvers in versions post-2020.[5]Everyday and general uses
Fruit and plant seeds
In botany and common usage, a pip denotes the small, hard seed contained within the fleshy core of certain fruits, particularly pome fruits such as apples (Malus domestica) and pears (Pyrus communis), where multiple pips (typically 5–10 per fruit) develop from the ovary.[6][7] These seeds are endosperm-rich structures capable of germination under suitable conditions, though apple pips contain cyanogenic compounds like amygdalin, rendering them toxic if ingested in quantity due to hydrogen cyanide release upon mastication.[8] Citrus fruits, including oranges (Citrus sinensis) and lemons (Citrus limon), also feature pips, which are small, oval seeds embedded in the pulp or central axis, often numbering 10–20 per fruit in seeded varieties.[9] Pips differ from pits or stones, which refer to the lignified endocarp enclosing a single large seed in drupes like peaches (Prunus persica) or cherries (Prunus avium); pips lack this protective shell and occur in multiples, reflecting the fruit's aggregate seed structure rather than a solitary kernel.[9] This distinction arises from fruit morphology: pome pips form in a syncarpous ovary, while drupe pits protect the seed in a monocarpellary structure.[10] The term originates from Old French pepin (13th century), denoting a seed of fleshy fruit, evolving into Middle English by the 14th century.[11] Beyond fruits, "pip" extends to certain plant propagation structures resembling seeds, such as the rhizomatous rootstocks of lily-of-the-valley (Convallaria majalis), where individual pips are offset segments used for clonal reproduction, producing new shoots from dormant buds.[12] Similarly, peonies (Paeonia spp.) employ pips as divided root sections for vegetative propagation, each containing meristematic tissue for regrowth.[10] These pips enable efficient multiplication without sexual reproduction via true seeds, a practice documented in horticultural texts since the 18th century.[7]Gaming marks and measurements
In playing cards, a pip refers to each instance of the suit symbol—such as hearts, diamonds, clubs, or spades—that indicates the card's rank, with numbered cards featuring one to ten pips arranged in specific patterns, while face cards have decorative representations.[12] These pips originated from early card designs in the 15th century, evolving from simple dot-like markers to stylized suits for easier counting and distinction during gameplay.[13] On dice, pips are the indented dots numbering from one to six on each face of a standard six-sided die, arranged in opposing sums of seven (e.g., one opposite six) to facilitate quick value assessment and prevent cheating through uniform weighting.[14] This configuration enhances visibility from various angles, a design choice dating back to ancient dice prototypes but standardized in modern Western dice by the 19th century for fairness in games like craps or Yahtzee.[14] Dominoes employ pips as dots on each half of a tile, ranging from zero (blank) to six or higher in extended sets like double-nine or double-twelve, where the total pips determine matching rules and scoring in games such as Mexican Train or standard block dominoes.[15] The blank pip, or zero, adds strategic depth by allowing versatile plays without numerical value, a feature consistent across traditional Chinese and European domino sets developed over centuries.[15] In backgammon, pip count serves as a measurement of positional advantage, calculated as the total number of pips—each representing one point on the board—from all a player's checkers to their home board, typically aiming for a lower count to win races against opponents.[16] A difference of seven or more pips often signals a strong racing lead, though adjustments for blots, primes, and gammons refine strategic decisions mid-game, as evidenced in professional analyses where precise counting via anchors or the "effective pip count" formula (total pips minus wasted moves) predicts outcomes with high accuracy.[17] This metric, rooted in the game's 17th-century codification, underscores causal board control over random rolls.[18]Idioms and slang expressions
In British English, the idiom give someone the pip refers to causing annoyance or irritation, often implying a mild but persistent displeasure akin to a low-grade malaise.[19] This expression derives from "the pip," a 15th-century term for a respiratory disease in birds characterized by mucus buildup and lethargy, which by the 19th century metaphorically extended to human states of peevishness or minor illness before evolving into slang for vexation; the first recorded use in the sense of irritation dates to 1896.[19][20] Another prevalent British idiom is pipped at the post, meaning to be narrowly defeated at the final moment, particularly in competitions or races.[21] Originating in 19th-century horse racing terminology, "pip" in this context likely stems from the act of a chick "pipping" (pecking through) its eggshell to emerge victorious, symbolizing a last-second breakthrough, though some etymologists link it to military slang for a fatal shot; the phrase gained currency in the 1870s and emphasizes defeat by a slim margin despite leading.[22][23] The exclamation pip pip, a dated British colloquialism, serves as a cheerful farewell or expression of enthusiasm, primarily associated with upper-class or affected speech from the early 20th century.[24] It imitates the short, repeated honk of an early automobile horn, evoking a jovial send-off, and appeared in print as early as 1901, though its usage has declined sharply since the mid-20th century.[25] In American English slang, a pip denotes something or someone exceptionally fine, admirable, or noteworthy, often with an undertone of eccentricity or irony for a "real character" who stands out—positive or troublesome.[26] This sense, attested from the 1890s, draws from "pip" as a seed's vitality or a small but potent element, evolving into colloquial praise for vibrancy or appeal, as in "she's a pip" for an engaging, lively individual.[26]Military and signaling
Rank insignia
In the British Army and other Commonwealth militaries, a pip denotes a small, star-shaped insignia—typically embroidered or metallic, resembling a four-pointed star—worn on an officer's epaulettes, shoulder straps, or slides to signify commissioned rank. Derived from the Bath Star of the Most Honourable Order of the Bath, a British chivalric order established in 1725, the pip serves as a simplified emblem for uniform badges, distinguishing junior officers through quantity and placement rather than complex heraldry.[27][28] Pips primarily denote ranks among subalterns and captains, with variations by service branch and era. In the British Army during World War I, for example, second lieutenants wore one pip on each shoulder strap, while lieutenants displayed two pips per strap; captains added a third pip or combined pips with other markers.[29] Higher ranks incorporate pips alongside crowns (representing St. Edward's Crown) or bars, such as majors wearing a single crown above crossed blades, but the core pip system persists for foundational officer identification across infantry, armored, and support units. This structure ensures quick visual recognition in field conditions, with materials ranging from bullion wire for dress uniforms to subdued fabric for combat.[30] The use of pips extends to air forces like the Royal Air Force, where pilot officers employ similar stars on rank slides, and to Commonwealth armies such as Australian and Canadian forces, which retained the British model post-independence. Originating in the early 19th century as formalized shoulder distinctions—superseding earlier sash and gorget identifiers—the system emphasizes hierarchy through minimalistic, durable symbols, avoiding overly ornate designs that could hinder mobility.[28] Regimental variations exist, with elite units like the Guards sometimes substituting stars from other orders (e.g., the Garter), but the standard pip remains ubiquitous for denoting commissioned status over non-commissioned ranks, which use chevrons or stripes.[31]Radar and detection signals
In radar systems, a pip refers to the visual indication of a received echo signal on a display scope, representing the detection of a target or object. This manifestation occurs when a transmitted radar pulse reflects off a distant object and returns to the receiver, producing a brief deflection or "blip" on the indicator, typically appearing as a triangular or peaked waveform aligned with the sweep line.[32] The pip's position along the time base or range axis corresponds to the target's distance, determined by the round-trip propagation time of the electromagnetic wave, while its angular position relative to the sweep indicates the bearing.[33] The shape and intensity of the pip vary based on factors such as target size, radar cross-section, atmospheric conditions, and signal processing. Larger targets, like ships or aircraft, often produce broader or more persistent pips due to stronger echoes, whereas smaller or distant objects yield fainter, sharper peaks that may fluctuate with sea clutter or noise.[34] In Plan Position Indicator (PPI) displays, common in naval and air defense radars since World War II, the pip is "painted" as the rotating antenna beam sweeps across the target, with the echo strength modulating its brightness or size. Early pulse radars, such as those developed in the 1930s and deployed by 1940, relied on these pips for initial target acquisition, enabling operators to distinguish genuine echoes from noise through visual thresholding or basic integration techniques.[35] Detection reliability hinges on the signal-to-noise ratio, where a detectable pip must exceed background clutter or receiver noise by a sufficient margin, often quantified in terms of probability of detection versus false alarms. For instance, in operational U.S. Navy radars like the SCR-268 of 1940, pips were interpreted manually, with operators adjusting gain to optimize visibility while suppressing interference.[36] Modern systems incorporate digital signal processing to enhance pip resolution, such as through pulse compression or coherent integration, reducing the subjectivity of analog displays but preserving the fundamental pip as the core detection artifact.[37]Business and finance
Percentage in point (forex trading)
In foreign exchange (forex) trading, a pip, short for "percentage in point" or "price interest point," denotes the smallest standardized unit of price movement for a given currency pair, typically representing a change of 0.0001 in the exchange rate for most pairs quoted to four decimal places.[38][39] This unit equates to one basis point or 1/100th of 1%, enabling traders to quantify minute fluctuations in value between two currencies.[39][40] For currency pairs where the quote currency is not the Japanese yen (JPY), such as EUR/USD, a pip corresponds to the fourth decimal place; for instance, a shift from 1.1050 to 1.1051 constitutes one pip.[41][39] In contrast, JPY-involved pairs like USD/JPY use a pip value of 0.01 due to yen's lower valuation, with quotes typically to two decimal places; thus, a move from 110.50 to 110.51 is one pip.[41][42] Some brokers extend precision with "pipettes," or fractional pips, equivalent to 1/10th of a pip (fifth decimal for non-JPY pairs), allowing for finer tracking of spreads and movements.[41] Pips serve as the foundational metric for assessing trade profitability or loss, with the monetary value of a pip varying by position size (e.g., standard lot of 100,000 units), currency pair, and account denomination.[43] The pip value can be calculated as (0.0001 / exchange rate) × trade size for pairs where the account currency matches the quote currency; for a standard lot in EUR/USD at 1.1000, one pip equals approximately €10.[40][42] Adjustments apply when currencies differ, often requiring conversion at prevailing rates; for USD/JPY, the formula adapts to 0.01 / rate × size, yielding about $9.09 per pip on a standard lot at 110.00.[41] Traders leverage pip-based risk management, such as setting stop-losses at 20-50 pips, to control exposure amid leverage, where amplified positions magnify pip impacts.[38][44] Introduced amid the evolution of electronic forex platforms in the late 1990s and early 2000s, pips standardized quoting practices across interbank and retail markets, replacing coarser tick sizes and facilitating algorithmic trading.[40] Daily forex volume exceeds $7.5 trillion as of 2022, with pips underpinning volatility metrics like average true range, often 50-100 pips for major pairs during active sessions.[42] While universally adopted, pip conventions may vary slightly by broker for exotic pairs or metals like gold (XAU/USD, where one pip is 0.01), underscoring the need for platform-specific verification.[45]Performance improvement plans
A performance improvement plan (PIP), abbreviated from the term pip in some business contexts, constitutes a formal, written strategy implemented by employers to rectify documented underperformance in employees. It delineates specific, measurable goals, actionable steps, timelines—typically 30 to 90 days—and resources such as training or mentoring to facilitate improvement.[46][47] The process begins with identifying performance gaps through prior evaluations, followed by collaborative development of the plan involving the employee, manager, and often HR, to ensure alignment and buy-in.[48][49] Regular progress reviews, conducted bi-weekly or monthly, track adherence and adjust expectations as needed, culminating in a final assessment determining continuation, extension, or termination.[50] Best practices emphasize objectivity, with metrics tied to job responsibilities—such as sales targets or error rates—and avoidance of vague language to mitigate disputes.[51] Documentation throughout serves dual purposes: supporting employee development and providing legal evidence of due diligence in cases of dismissal, particularly under at-will employment doctrines or anti-discrimination laws.[49][52] Empirical assessments reveal PIPs' limited efficacy, with many functioning as structured pathways to separation rather than recovery tools; employee retention post-PIP often hovers below 50%, attributable to demotivation, skill deficits beyond remediation, or mismatched role fit.[53][54] HR analyses highlight that success hinges on early intervention and genuine commitment, yet systemic biases in implementation—such as inconsistent application across demographics—can undermine credibility and invite litigation risks.[55] Alternatives like ongoing coaching or role reassignment may yield higher returns for salvageable cases, underscoring PIPs' role as a last-resort measure rather than a panacea.[56][57]Government and welfare systems
Personal Independence Payment (UK)
Personal Independence Payment (PIP) is a non-means-tested benefit administered by the Department for Work and Pensions (DWP) in Great Britain to assist individuals aged 16 to State Pension age with extra living costs arising from long-term physical or mental health conditions or disabilities that cause difficulties in daily activities or mobility.[58] It replaced Disability Living Allowance (DLA) for working-age claimants as part of the Welfare Reform Act 2012, aiming to target support more effectively based on functional needs rather than medical diagnosis alone.[59] Introduced on 8 April 2013 in a limited rollout in parts of northern England, the full national rollout for new claims completed by 2017, with existing DLA recipients reassessed gradually.[60] Eligibility requires claimants to be 16 or over but under State Pension age, reside in Great Britain (with Northern Ireland operating a parallel scheme), and have a condition expected to last at least nine months in the next 12 (or three months if terminally ill), resulting in substantial difficulty—defined as needing prompting, supervision, assistance, or aids more than 50% of days—with at least one daily living activity or mobility.[61] Claims begin with a 'How your disability affects you' form assessing 12 activities across two components: daily living (preparing food, eating, managing therapy, washing, managing toilet needs, dressing, communicating, reading, engaging with others, managing money) and mobility (planning journeys, moving around).[61] Awards are not automatic and exclude those in legal detention or hospital for extended periods under certain conditions.[61] The assessment process involves an independent health professional reviewing the form, evidence, and conducting an interview—typically by phone, video, or in-person lasting about one hour—to score functional limitations on a points system: 0-4 points per descriptor per activity, with thresholds of 8+ points for standard rate and 12+ for enhanced rate in each component.[62] Decisions are made by DWP officials, with possible mandatory reconsiderations and appeals to tribunals, where overturn rates have historically exceeded 60% in some periods, indicating initial assessments often underestimate needs.[63] Awards range from nine months to ongoing, with light-touch reviews for stable conditions; payments are tax-free, not dependent on work status, and can include special rules for terminal illness granting enhanced daily living without full assessment.[64] As of July 2024, over 3.5 million people received PIP, with weekly rates for 2025/26 set at £29.40 standard and £110.20 enhanced for mobility, and £72.65 standard and £108.55 enhanced for daily living, totaling up to £184.30 maximum combined.[60] [65] The system has faced criticism for assessment inaccuracies, with reports of over 300,000 claimants owed arrears due to errors in reviews, averaging £2,771 per case, and broader concerns that stringent criteria and provider inconsistencies—often from private contractors—lead to undue stress and denials, though official fraud rates remain low at under 0.5%.[66] [67] Government responses emphasize refining assessments for better targeting amid rising caseloads, projected to cost £25 billion annually by 2029 without reform.[63]Medicine and biology
Poly Implant Prothèse breast implants
Poly Implant Prothèse (PIP) was a French manufacturer of silicone-filled breast implants, established in 1991 by Jean-Claude Mas and commencing production in 1997.[68] The company gained market share by offering lower-cost implants, which were certified under the European CE mark but later found to incorporate non-medical-grade silicone gel, sourced from industrial suppliers to reduce expenses.[69] This substitution violated regulatory standards for medical devices, as the silicone lacked the purity and biocompatibility required for human implantation.[70] Defects in PIP implants surfaced in public reports as early as 2006 and 2007, prompting investigations by French authorities.[71] By 2010, the French Agency for the Safety of Health Products (Afssaps, now ANSM) identified the use of unapproved silicone, leading to a nationwide suspension and recall of PIP products on March 30, 2010.[72] Similar actions followed internationally: the United Kingdom withdrew PIP implants in September 2010 after confirming fraudulent manufacturing; Australia recalled non-implanted units in April 2010; and Brazil imposed a full ban on December 30, 2011.[70][73] The scandal affected an estimated 400,000 women across 55 countries, with notable concentrations including 30,000 in France, 40,000-52,000 in the UK, and 25,000 in Brazil.[74][72] PIP implants exhibited rupture rates 2 to 6 times higher than standard silicone devices, with overall failure rates reaching approximately 23% based on post-recall data.[70][75] Ruptures often resulted in local complications such as silicone leakage, siliconomas (nodule-forming granulomas), tissue irritation, and capsular contracture, necessitating explantation surgeries.[76] However, multiple expert reviews, including those from the UK Department of Health and the European Commission, found no evidence linking PIP silicone exposure to increased risks of cancer, autoimmune diseases, or systemic toxicity beyond localized effects.[77][78][79] In December 2013, a Marseille court convicted Jean-Claude Mas of aggravated fraud for knowingly distributing defective implants, sentencing him to four years in prison (two years suspended), a €75,000 fine, and a lifetime ban from medical device activities; the ruling was upheld on appeal in 2016.[80][81] The case highlighted regulatory lapses in pre-market certification and post-market surveillance, as PIP evaded detection despite over 260 adverse event reports to French authorities between 2001 and 2009.[82] Compensation funds were established in affected countries, though access varied, with ongoing litigation in some jurisdictions as late as 2023.[83] Mas died in 2019 while evading full imprisonment.[84]Avian disorders
In veterinary pathology, "pip" denotes an older designation for a respiratory condition primarily affecting poultry, characterized by a white scale, horny patch, or discoloration (often blackening) at the tip of the tongue.[85] This manifestation results from chronic mouth breathing induced by nasal obstruction, typically secondary to infections causing catarrhal inflammation or mucus accumulation in the upper respiratory tract.[12] Common underlying causes include roup (a form of avian infectious coryza or diphtheria-like tracheitis) or other bacterial pathogens such as Avibacterium paragallinarum, leading to blocked nostrils and forced oral respiration that desiccates the tongue tip.[86] Affected birds exhibit symptoms such as thick mucus discharge from the mouth and throat, labored breathing, reduced appetite, lethargy, and potential dehydration, with mortality rising if the primary infection progresses untreated.[12] The condition was historically viewed as contagious due to the infectious nature of precipitating agents, spreading via direct contact or aerosols in confined flocks, though modern diagnostics emphasize identifying specific etiologies like infectious coryza over the symptomatic "pip" label.[85] Prevalence was noted in 19th- and early 20th-century poultry husbandry, correlating with poor ventilation and overcrowding, but the term has largely fallen out of use in contemporary avian medicine, supplanted by precise pathogen-based classifications.[87] Treatment focuses on the root respiratory infection, incorporating antibiotics (e.g., sulfonamides or tetracyclines for susceptible bacteria), supportive care like hydration and isolation, and improved housing to enhance airflow and reduce humidity that exacerbates mucus buildup.[88] Prevention relies on vaccination against key respiratory diseases, strict biosecurity to limit pathogen introduction, and routine monitoring for early nasal discharge or swelling, as delays in intervention can elevate flock losses to 10-20% in outbreaks of associated conditions.[88] While not a standalone diagnosis today, "pip" illustrates historical observations of symptom clustering in avian respiratory syndromes, underscoring the importance of causal pathogen isolation for effective management.Computing and software
Python package installer
Pip is a command-line package installer and manager for the Python programming language, enabling users to install, upgrade, and remove software packages primarily from the Python Package Index (PyPI). Written in Python itself, it serves as the standard tool for dependency management in Python projects, supporting operations such as resolving dependencies, installing from source distributions or wheels, and handling virtual environments.[2][89] The tool is invoked typically viapython -m pip to associate it with a specific Python interpreter, avoiding conflicts in multi-version setups.
Originally developed by Ian Bicking as pyinstall in 2008, pip emerged as a more user-friendly alternative to the existing easy_install tool, which had limitations in dependency resolution and uninstallation capabilities. Bicking, known for creating virtualenv, released pip to address pain points in Python packaging, building on the setuptools framework while introducing improvements like better support for version specifiers and editable installs. By 2010, pip reached version 1.0, and it was adopted under the Python Packaging Authority (PyPA), a working group formed to standardize Python packaging tools. The project's repository is maintained on GitHub by PyPA, with ongoing development focusing on security enhancements, such as hash checking for downloads, and compatibility with modern build backends like those defined in PEP 517.[90][91]
Pip's integration into Python distributions marked a significant milestone for accessibility. Python 3.4, released in 2014, included pip by default through the ensurepip module, which provides bootstrapping logic to install or upgrade pip if absent, as outlined in PEP 453 accepted that year. This explicit inclusion extended to Python 2.7.9 and later in the 2.x series, reducing setup friction for users and establishing pip as the recommended installer in official documentation. Features like pip freeze for generating requirements files and pip check for dependency integrity have evolved to support reproducible builds, though pip does not handle binary dependencies or non-Python code, often requiring complementary tools like conda for such cases.[92] As of 2025, pip version 24.x and later emphasize secure installations via options like --require-hashes and integration with keyring for credential management.