Cast
The English word "cast" has multiple meanings across various fields. In the performing arts, it refers to the group of performers portraying characters in a production. Other uses include the manufacturing process of shaping materials by pouring into molds (see Manufacturing and Crafts section), a rigid medical dressing for immobilization (see Medicine and Biology), throwing or projecting in sports and recreation, geological formations, computational functions, and more, as detailed in subsequent sections. In the performing arts, a cast is the group of actors, singers, dancers, or other performers who collectively portray the characters and elements of a production, such as a play, musical, film, television show, or opera, bringing the scripted narrative to life through their interpretations and performances. This ensemble is essential to realizing a director's vision, as the selection and dynamics among cast members directly shape the emotional depth, authenticity, and overall impact of the work.[1] The process of forming a cast, known as casting, occurs during the pre-production phase and involves auditions, callbacks, and negotiations to match performers' skills, physical attributes, vocal ranges, and interpretive abilities to specific roles outlined in the script or score.[1] Casting directors, often working alongside producers and directors, evaluate candidates based on criteria like prior experience, chemistry with other performers, and alignment with the production's thematic or stylistic goals, ensuring a balanced ensemble that supports the story's progression.[1] In modern practice as of the 2020s, this can include open calls, agent submissions, self-tapes, and diverse hiring initiatives to promote inclusivity across race, gender, and ability.[2] Casting practices have evolved significantly over time. Professional guilds emerged in medieval Europe for religious and civic dramas, while 19th-century American theater saw the rise of star-driven systems, where salaries and contracts reflected emerging commercial structures.[3][4] By the 20th century, the rise of film and television amplified typecasting—assigning performers to recurring archetypes based on appearance or past roles—which streamlined production but sparked debates over artistic limitations and stereotypes, particularly in musical theater and Hollywood.[2] In the 21st century, casting emphasizes equity and innovation, with approaches like "coalitional casting" allowing flexible interpretations of identity to challenge traditional boundaries and reflect societal values.[5] The significance of the cast extends beyond individual roles to the collective synergy that drives rehearsals, improvisations, and live interactions, influencing audience engagement and cultural discourse; for instance, diverse casts in productions like Broadway musicals have advanced social progress by normalizing underrepresented narratives.[2] Notable examples include celebrity casting to boost ticket sales, as seen in Broadway revivals drawing from film stars to blend media synergies,[6] or ensemble-driven works like Shakespeare's plays, where interchangeable roles highlighted repertory company traditions.[7] Ultimately, a well-cast production fulfills artistic intent and preserves performing arts as a mirror of human experience across eras.[8]Performing Arts
Theater and Film
In theater and film, the term "cast" refers to the ensemble of actors who portray the characters in a script, collectively bringing the narrative to life through performance. This group includes performers assigned to specific roles, ranging from principal characters to background figures, and is essential for realizing the director's vision in stage productions or on-screen adaptations. The cast is typically assembled during pre-production to ensure cohesion in acting styles and chemistry among performers.[1] The historical evolution of casting traces back to ancient Greece, where dramatic festivals like the City Dionysia in Athens around 534 BCE featured competitions among playwrights and performers, with winners selected by judges to enact tragedies and comedies, often limited to male citizen actors portraying all roles. Over centuries, this practice shifted through Roman theater, medieval mystery plays, and Renaissance revivals, where troupe leaders or directors chose performers based on guild affiliations or patronage. By the 19th century, professional theater in Europe and America formalized casting under directors, but it was not until the early 20th century in Hollywood that dedicated casting directors emerged as key figures; for instance, Lynn Stalmaster became the first to receive solo screen credit for casting in the 1968 film The Thomas Crown Affair, marking a professionalization of the role in film.[9][10] The casting process involves auditions, where actors perform monologues, scenes, or improvisations to demonstrate suitability for roles; successful candidates may receive callbacks for further evaluation, often including chemistry reads with potential co-stars. Roles within the cast are categorized as leads (protagonists driving the plot), supporting characters (key allies or antagonists with significant arcs), and ensemble members (who contribute to group dynamics without dominating screen or stage time). Typecasting occurs when actors are repeatedly assigned similar roles due to physical appearance, prior successes, or market perceptions, potentially limiting career versatility, as seen in historical patterns where performers were pigeonholed into genres like Westerns or comedies. Open casting calls invite submissions from any interested actors, democratizing access, while the "casting couch" euphemism describes exploitative demands for sexual favors in exchange for roles, a practice documented since the 1930s in Hollywood but increasingly condemned through industry reforms.[1][11][12] Post-2020, diversity in casting has advanced significantly, influenced by movements like #OscarsSoWhite and Black Lives Matter, with reports showing variation in representation; for instance, people of color held 43.1% of speaking roles in top-grossing films of 2021, but lead roles declined to 25.2% in 2024, while films with 41-50% people of color in casts achieved the highest median global box office of $234.6 million, outperforming less diverse ensembles.[13][14] Key examples include Broadway productions like Hamilton (2015), which employed color-conscious casting to feature diverse actors in historical roles, and Hollywood ensemble films such as Ocean's Eleven (2001), where a large cast of stars shared equal narrative weight in a heist plot, exemplifying balanced group performances. These practices prioritize inclusive representation while maintaining artistic integrity.[15]Music
In music, the term "cast" refers to the ensemble of performers, particularly singers, assembled for operas, musicals, or recordings, where roles are assigned based on vocal capabilities and artistic fit. Directors in opera and musical theater audition and select singers to form the cast, ensuring a balance of voice types such as sopranos, tenors, and baritones to suit the score's demands.[16] This practice emphasizes the auditory focus, distinguishing it from broader performing arts by prioritizing harmonic and melodic integration over dramatic staging.[17] Historically, in classical music and Italian opera, casting has involved assigning specific voice types to roles, a tradition rooted in the Baroque era where skilled singers, including castrati, were chosen for their virtuosity and range to convey emotional depth in works like those of Handel.[18] This evolved from Renaissance vocal consorts, small groups of singers performing polyphonic music like madrigals, where ensemble size and vocal blending across ranges were key to texture and expression.[19] By the Classical period, larger opera casts incorporated choruses and soloists, with casting decisions influencing the opera's overall sonority, as seen in Mozart's ensembles balancing high and low voices for dramatic contrast.[20] In contemporary musical theater, casting continues this lineage, selecting performers for band lineups or vocal ensembles based on range and timbre to achieve genre-specific sounds, from rock-infused scores to orchestral accompaniment.[21] In modern contexts, cast recordings capture the ensemble's performance of musical scores in studio settings, preserving the original vocal and instrumental interpretations for albums like those of Broadway shows, which document the cast's chemistry without live audience elements.[22] While brief, this extends to music production where "cast" occasionally denotes collaborative performer lineups in specialized recordings, though the emphasis remains on live and staged musical ensembles.[22]Manufacturing and Crafts
Metalworking
Casting in metalworking refers to a manufacturing process where molten metal is poured into a mold cavity, allowed to solidify, and then removed to create a desired shape. This technique enables the production of complex geometries that would be difficult or costly to achieve through other methods such as machining or forging.[23] Common types of metal casting include sand casting, die casting, investment casting, and centrifugal casting. In sand casting, a mold is formed from compacted sand around a pattern, offering versatility for large parts and low tooling costs. Die casting involves injecting molten metal under high pressure into a reusable steel mold, ideal for high-volume production of precise components. Investment casting, also known as lost-wax casting, uses a wax pattern coated in ceramic to create intricate shapes with excellent surface finish. Centrifugal casting rotates the mold at high speeds to distribute molten metal evenly, producing tubular parts with dense structures free of voids.[24] The process typically involves several key steps: melting the metal in a furnace to achieve a liquid state, pouring the molten material into the prepared mold, allowing it to cool and solidify, and finally finishing the casting through removal from the mold, cleaning, and additional treatments like machining or heat treatment. Materials commonly used include ferrous metals such as cast iron and steel, which provide strength and durability, as well as non-ferrous options like aluminum and its alloys for lightweight applications, and copper-based alloys for corrosion resistance. Gray iron is favored for its fluidity and low cost in producing intricate shapes, while aluminum alloys enable complex designs in high-performance components.[25][26] The historical development of metal casting traces back to around 3200 BCE in Mesopotamia, where the oldest known casting—a copper frog—was produced using basic molds. By 3000 BCE, bronze casting emerged in the same region, enabling the creation of tools, weapons, and ornaments that marked the Bronze Age. Over millennia, techniques advanced through civilizations in Egypt, China, and Europe, incorporating improved furnaces and mold materials; by the Industrial Revolution, casting became central to mechanized production in modern foundries, which now employ automated systems for efficiency and scale.[27][28] Applications of metal casting span diverse industries, including the production of automotive parts such as engine blocks, cylinder heads, and transmission housings, which benefit from the process's ability to form large, complex structures. In machinery, it is used for components like gears, valves, and pump housings that require durability under load. Jewelry manufacturing often employs investment casting for intricate designs in gold, silver, and platinum alloys, achieving fine details unattainable by other means.[29][24][30] Metal casting offers advantages such as cost-effectiveness for high-volume production, the ability to create near-net shapes that minimize material waste, and versatility in handling a wide range of metals and sizes. However, it is prone to defects like porosity—gas pockets that reduce strength—and shrinkage during cooling, which can distort dimensions if not controlled through proper gating and riser design. These challenges often necessitate post-processing, potentially increasing overall costs compared to simpler fabrication methods.[31][32]Sculpture and Modeling
In sculpture and modeling, casting refers to the artistic process of creating replicas of three-dimensional forms using molds, allowing sculptors to replicate intricate details while emphasizing creative expression over industrial replication. This technique enables the production of durable works in materials like bronze, ceramic, or plaster, preserving the artist's original vision through controlled duplication. Unlike mass production, casting in art prioritizes limited editions and hand-finishing to maintain uniqueness and intentional imperfections that convey emotional depth.[33] Key techniques include lost-wax casting, primarily for metals like bronze; slip casting for ceramics; and plaster casting for direct modeling. Lost-wax casting, known as cire perdue, begins with an artist's model in clay or plaster, from which a flexible mold is made to form a wax positive; this wax is then encased in refractory material, melted out, and replaced with molten metal poured at over 2,000°F, followed by chasing and patination for surface refinement.[33][34] Hollow variants, using a clay core, allow for larger sculptures cast in sections and assembled, reducing material use while capturing fine details like drapery or musculature. Slip casting involves pouring liquid clay slip into porous plaster molds, where water absorption forms a solid wall; excess slip is drained after 20-30 minutes, and the greenware is removed, dried, and fired for ceramic pieces with smooth, uniform surfaces ideal for decorative glazing.[35] Plaster casting uses Plaster of Paris mixed with water and poured into piece molds made from the original sculpture; it sets in about 45 minutes, is demolded, and often serves as an intermediate step for further casting or as a finished work, valued for its quick setup and ability to replicate textures.[36] Common materials encompass Plaster of Paris for molds and casts due to its absorbency and workability; clay slips deflocculated with additives for fluidity in ceramics; waxes refined for detail in lost-wax processes; and resins or polymers for modern lightweight alternatives. The overall process—mold-making from an original, pouring the casting material, and demolding—demands precision to avoid defects like air bubbles, with post-processing such as trimming, firing, or patination enhancing aesthetic qualities. In historical contexts, Renaissance sculptors like Michelangelo employed lost-wax methods for bronze works such as Benvenuto Cellini's Perseus with the Head of Medusa (1545–1554), adapting ancient Greek techniques to achieve lifelike anatomy and dynamic poses in limited editions.[37] Auguste Rodin extensively used lost-wax casting in the late 19th century, preferring it for its fidelity to his expressive clay models; for instance, in The Gates of Hell (1880-1917), over 200 figures were cast via gelatin molds poured with wax, then invested and bronzed, allowing multiple editions like the 300+ casts of The Kiss while retaining tactile immediacy.[38][39] Contemporary artists integrate 3D printing to assist casting, printing wax or resin patterns directly from digital scans for complex geometries unattainable by hand, such as lattice structures in bronze sculptures. This hybrid approach, as seen in foundry collaborations for awards like the Bambi or custom public art, streamlines prototyping and enables rapid iterations while preserving traditional finishing like chiseling and patination.[40] Unlike industrial mass production, which focuses on efficiency and uniformity, artistic casting underscores limited runs—often editioned and signed—to highlight the sculptor's intent, variability in patinas, and narrative depth, ensuring each piece retains individual character.[41]Medicine and Biology
Orthopedic and Medical Devices
In orthopedics, a cast is a rigid medical device designed to immobilize fractured bones, injured joints, or soft tissues, promoting healing by maintaining alignment and reducing movement. Typically constructed as a shell of plaster or fiberglass encircling the affected area, casts provide circumferential support to prevent displacement while allowing for weight-bearing in some lower extremity designs.[42][43] The use of casts traces back to the mid-19th century, when Dutch army surgeon Antonius Mathijsen developed the first plaster of Paris bandage in 1852, applying it by rubbing the powder onto gauze for rapid setting and effective immobilization. This technique gained prominence during the Crimean War (1853–1856), where it successfully stabilized fractures in battlefield conditions, marking a shift from earlier methods like wooden splints or starch bandages. By the 1970s, traditional plaster casts, which involved cotton underlayment and water-activated setting, were standard for fracture care, but their weight and moisture absorption prompted innovations. In the late 1970s and 1980s, synthetic fiberglass materials emerged as lighter, more durable alternatives, with water-activated bandages introduced in 1978 by Cutter Biomedical, reducing skin irritation and improving patient comfort. Modern advancements include waterproof casts developed in the 1990s, featuring liners like Gore-Tex to allow showering without removal.[44][45][46][47] Common types of orthopedic casts vary by location and injury severity, including short-arm casts for wrist or forearm fractures, which extend from below the elbow to the hand, and long-arm casts that reach the upper arm for elbow or humerus injuries. Lower extremity options encompass short-leg casts for ankle or foot issues, long-leg casts up to the thigh for tibial fractures, and cylinder casts that fully encircle the limb without end caps for rotational stability. Specialized variants, such as shoulder spica casts for proximal humerus breaks or hip spica casts for pelvic fractures, incorporate the torso to limit motion at multiple joints. Synthetic fiberglass casts, prevalent since the 1980s, offer advantages like radiolucency for X-ray imaging and reduced bulk compared to plaster.[48][49][43] The application process begins with a stockinette layer for skin protection, followed by 2–3 layers of soft cotton padding to cushion pressure points and absorb moisture, preventing sores. The casting material—plaster strips soaked in water or fiberglass rolls activated by moisture—is then molded around the limb in overlapping layers, setting within minutes for plaster (full hardness in 24–48 hours) or faster for synthetics, with the clinician ensuring proper alignment via manual reduction if needed. Removal typically involves an oscillating cast saw to cut along the edges, followed by spreading and peeling away the material, a procedure that requires caution to avoid skin burns from the blade's vibration. Potential complications include compartment syndrome, a surgical emergency from swelling-induced pressure buildup, which may necessitate immediate cast bivalving (splitting) to relieve tension by up to 85%; other risks encompass thermal burns from exothermic setting reactions, pressure ulcers from tight spots, and skin infections if hygiene is neglected.[50][51][52][53] Splints and braces serve as precursors or alternatives to full casts; splints provide partial immobilization with flexible or rigid materials for initial swelling management or minor injuries, while braces offer adjustable support for post-healing rehabilitation, contrasting the rigid, non-removable nature of casts for acute fractures.[43][54]Biological Structures
In biology, earthworm casts refer to the coiled mounds of soil excreted by earthworms after they ingest and process organic matter and mineral particles through their digestive systems. These casts are rich in nutrients, containing up to five times more nitrogen, seven times more phosphorus, and eleven times more bacteria compared to the surrounding soil, thereby enhancing soil fertility and supporting plant growth.[55] Earthworms produce these casts as they burrow, improving soil aeration by creating pores and channels that facilitate water infiltration and root penetration, which in turn boosts microbial activity and nutrient cycling in ecosystems.[56] Ecologically, earthworm casts play a vital role in soil health by breaking down organic detritus and stabilizing soil structure, though excessive casting on turf surfaces can lead to uneven terrain and reduced playability in managed landscapes. As of 2023, studies note that rising temperatures may increase casting rates, potentially amplifying soil turnover in warming ecosystems.[57][58] Urinary casts are cylindrical microscopic structures formed in the distal convoluted tubules and collecting ducts of the kidneys, composed primarily of Tamm-Horsfall mucoprotein that aggregates with cells or debris in urine. These casts are classified by composition, with hyaline casts appearing as clear, colorless cylinders indicating reduced urine flow often due to dehydration, exercise, or diuretic use, while granular casts—formed from degenerated cellular elements—signal tubular damage in conditions like acute kidney injury or chronic renal disease.[59] Red blood cell casts, for instance, denote glomerular bleeding associated with glomerulonephritis.[60] In nephrology, microscopic examination of urine sediment for these casts provides diagnostic insight into renal pathology, as their presence and type help differentiate prerenal, renal, and postrenal causes of kidney dysfunction. As of the 2020s, integration with automated urine analyzers has improved detection accuracy for early intervention.[61][62] In insects and other arthropods, casts manifest as exuviae, the shed remnants of molted exoskeletons left behind during ecdysis, the process by which organisms grow by discarding their rigid chitinous covering. These exuvial casts preserve the shape of the previous instar, offering clues to developmental stages, as seen in dragonfly nymphs emerging as adults or cicadas transitioning from nymph to imago.[63] The molting process exposes the soft new exoskeleton temporarily, making the organism vulnerable, but the discarded cast serves as a durable artifact for studying arthropod morphology and life cycles.[64] In paleobiology, biological casts like those from ancient annelids provide trace fossil evidence of early terrestrial and aquatic life, with structures dating back approximately 500 million years to the Cambrian period, illustrating burrowing behaviors and sediment processing that influenced prehistoric ecosystems.[65] These preserved casts reveal evolutionary adaptations in soil-dwelling organisms, contributing to our understanding of how bioturbation shaped ancient environments without direct body fossils.[66]Computing and Technology
Programming
In computer science, type casting refers to the explicit conversion of a value from one data type to another, allowing compatibility in operations where types differ.[67] This process is distinct from implicit conversions, which occur automatically without programmer intervention, and is essential for ensuring type safety and preventing runtime errors in statically typed languages.[68] For example, casting an integer to a floating-point number in C++ enables arithmetic operations that would otherwise be incompatible due to type mismatches.[69] Syntax for type casting varies by language but typically involves operators or constructor functions. In C++, the C-style cast uses parentheses around the target type, such as(float)myInt, while the safer static_cast operator provides static_cast<float>(myInt), which performs compile-time checks for valid conversions like numeric or pointer types without runtime overhead.[69] In Python, a dynamically typed language, explicit conversion relies on built-in functions like int("123") or float(5), which invoke the object's __int__ or __float__ methods to transform the value.[70] These mechanisms ensure the programmer explicitly acknowledges the conversion, reducing ambiguity compared to implicit handling.
Type casting encompasses several categories based on the relationship between source and target types. Widening conversions expand the type's range without data loss, such as promoting an int to double in numeric operations.[71] Narrowing conversions, conversely, restrict the range and may truncate information, like converting a double to int.[72] In object-oriented programming, upcasting treats a subclass instance as its superclass, often implicit and safe for polymorphism, while downcasting reverses this by explicitly converting a superclass reference to a subclass, requiring verification to avoid invalid accesses.[73]
Narrowing casts pose significant risks, including data loss where precision or magnitude is discarded—for instance, casting 3.14 to an integer yields 3, losing the fractional part.[71] Invalid downcasts can lead to undefined behavior, such as accessing non-existent methods, without runtime checks in operators like static_cast.[69] Historically, early languages like C relied heavily on implicit conversions, but post-1990s designs in C++ and similar languages shifted toward explicit casting to mitigate these hazards and improve code maintainability, as seen in the introduction of typed operators in the C++98 standard.[74]
Type casting finds practical applications across software domains. In application programming interfaces (APIs), it ensures parameter types match function signatures, such as converting user inputs to expected formats.[67] For graphics rendering, casts handle coordinate transformations between integer pixels and floating-point vectors, maintaining precision in rendering pipelines.[75] In database queries, SQL's CAST function converts column values for comparisons or outputs, like transforming strings to dates in analytical operations.