A listing or program listing is a printed

list A list is a Set (mathematics), set of discrete items of information collected and set forth in some format for utility, entertainment, or other purposes. A list may be memorialized in any number of ways, including existing only in the mind of t ...

of lines of

computer code Computer code may refer to: *Source code *Machine code *Bytecode Bytecode (also called portable code or p-code) is a form of instruction set designed for efficient execution by a software interpreter. Unlike human-readable source code, byte ...

digital Digital usually refers to something using discrete digits, often binary digits. Businesses *Digital bank, a form of financial institution *Digital Equipment Corporation (DEC) or Digital, a computer company *Digital Research (DR or DRI), a software ...

data Data ( , ) are a collection of discrete or continuous values that convey information, describing the quantity, quality, fact, statistics, other basic units of meaning, or simply sequences of symbols that may be further interpreted for ...

(in human-readable form).

Use cases

Listings are commonly used in

education Education is the transmission of knowledge and skills and the development of character traits. Formal education occurs within a structured institutional framework, such as public schools, following a curriculum. Non-formal education als ...

and computer-related

book A book is a structured presentation of recorded information, primarily verbal and graphical, through a medium. Originally physical, electronic books and audiobooks are now existent. Physical books are objects that contain printed material, ...

s to show examples of code. In the early days of programming, it was used to hand-check a program and as permanent storage. It was also common in 1970s and 1980s computer enthusiast magazines (for instance

Creative Computing ''Creative Computing'' was one of the earliest magazines covering the microcomputer revolution. Published from October 1974 until December 1985, the magazine covered the spectrum of hobbyist/home/personal computing in a more accessible format t ...

) and books like

BASIC Computer Games ''BASIC Computer Games'' is a compilation of type-in computer games in the BASIC programming language collected by David H. Ahl. Some of the games were written or modified by Ahl as well. Among its better-known games are '' Hamurabi'' and '' Su ...

for

type-in program A type-in program or type-in listing was computer source code printed in a home computer magazine or book. It was meant to be entered via the keyboard by the reader and then saved to cassette tape or floppy disk. The result was a usable game, ut ...

s. Today,

hard copy In information handling, the U.S. Federal Standard 1037C (Glossary of Telecommunication Terms) defines a hard copy as a permanent reproduction, or copy, in the form of a physical object, of any media suitable for direct use by a person (in par ...

listings are seldom used because display screens can present more lines than formerly, programs tend to be modular, storage in

soft copy Soft may refer to: * Softness, or hardness, a property of physical materials Arts and entertainment * ''Soft!'', a novel by Rupert Thomson, 1988 * Soft (band), an American music group * ''Soft'' (album), by Dan Bodan, 2014 * ''Softs'' (album), ...

is considered preferable to

, and digital material is easily transmitted via networks, or on disks or tapes. Furthermore, data sets tend to be too large to be conveniently put on paper, and they are more easily searched in soft-copy form. Assembly-code listings are occasionally analysed by programmers who want to understand how a compiler is translating their source code into assembly language. For example, the

GNU C Compiler The GNU Compiler Collection (GCC) is a collection of compilers from the GNU Project that support various programming languages, hardware architectures, and operating systems. The Free Software Foundation (FSF) distributes GCC as free software ...

(gcc) will produce an assembly code listing if it is invoked with the command-line option -S. Listings of computer programs are still important in

US patent law Under Law of the United States, United States law, a patent is a right granted to the inventor of a (1) process, machine, article of manufacture, or composition of matter, (2) that is novelty (patent), new, utility (patent), useful, and Invent ...

. They are defined as follows in the Manual of Patent Examining Procedure:Manual of Patent Examining Procedure 37 C.F.R. 1.96, http://www.bitlaw.com/source/37cfr/1_96.html, 9th Edition, March 2014

References

Source code Text editor features {{compu-prog-stub