Category
use is in rigorous analyses of algorithmic complexity.
Like many "firsts" in history, the first modern programming language is hard to identify. From the start, the restrictions of the hardware defined the language. Punch cards allowed 80 columns, but some of the columns had to be used for a sorting number on each card. FORTRAN included some keywords which were the same as English words, such as "IF", "GOTO" (go to) and "CONTINUE". The use of a magnetic drum for memory meant that computer programs also had to be interleaved with the rotations of the drum. Thus the programs were more hardware-dependent.
To some people, what was the first modern programming language depends on how much power and human-readability is required before the status of "programming language" is granted. Jacquard looms and Charles Babbage's Difference Engine both had simple, extremely limited languages for describing the actions that these machines should perform. One can even regard the punch holes on a player piano scroll as a limited domain-specific language, albeit not designed for human consumption.
The 1940s[edit]
In the 1940s, the first recognizably modern electrically powered computers were created. The limited speed and memory capacity forced programmers to write hand tuned assembly language programs. It was eventually realized that programming in assembly language required a great deal of intellectual effort and was error-prone.
In 1948, Konrad Zuse published a paper about his programming language Plankalkül. However, it was not implemented in his lifetime and his original contributions were isolated from other developments.
Some important languages that were developed in this period include:
1943 - Plankalkül (Konrad Zuse), designed, but unimplemented for a half-century
1943 - ENIAC, E lectric N umerical I ntegrator A nd C omputer, machine-specific codeset
appearing in 1948.[2]
1949 - 1954 — a series of machine-specific mnemonic instruction sets, like ENIAC's,
beginning in 1949 with C-10 for BINAC (which later evolved into UNIVAC).[3] Each codeset, or instruction set, was tailored to a specific manufacturer.
The 1950s and 1960s[edit]
In the 1950s, the first three modern programming languages whose descendants are still in widespread use today were designed:
FORTRAN (1955), the "FOR mula TRAN slator", invented by John Backus et al.;
LISP (1958), the "LIS t P rocessor", invented by John McCarthy et al.;
COBOL (1959), the CO mmon B usiness O riented L anguage, created by the Short Range Committee, heavily influenced by Grace Hopper.
Another milestone in the late 1950s was the publication, by a committee of American and European computer scientists, of "a new language for algorithms"; the ALGOL 60 Report (the "ALGO rithmic L anguage"). This report consolidated many ideas circulating at the time and featured two key language innovations:
nested block structure: code sequences and associated declarations could be grouped into blocks without having to be turned into separate, explicitly named procedures;
lexical scoping: a block could have its own private variables, procedures and functions,
invisible to code outside that block, i.e. information hiding.
Another innovation, related to this, was in how the language was described:
a mathematically exact notation, Backus-Naur Form (BNF), was used to describe the
language's syntax. Nearly all subsequent programming languages have used a variant of BNF to describe the context-free portion of their syntax.
Algol 60 was particularly influential in the design of later languages, some of which soon became more popular. The Burroughs large systems were designed to be programmed in an extended subset of Algol.
Algol's key ideas were continued, producing ALGOL 68:
syntax and semantics became even more orthogonal, with anonymous routines, a recursive typing system with higher-order functions, etc.;
not only the context-free part, but the full language syntax and semantics were defined
formally, in terms of Van Wijngaarden grammar, a formalism designed specifically for this purpose.
Algol 68's many little-used language features (e.g. concurrent and parallel blocks) and its complex system of syntactic shortcuts and automatic type coercions made it unpopular with implementers and gained it a reputation of being difficult. Niklaus Wirth actually walked out of the design committee to create the simpler Pascal language.
Some important languages that were developed in this period include:
1951 - Regional Assembly Language
1952 - Autocode
1954 - IPL (forerunner to LISP)
1955 - FLOW-MATIC (forerunner to COBOL)
1957 - FORTRAN (First compiler)
1957 - COMTRAN (forerunner to COBOL)
1958 - LISP
1958 - ALGOL 58
1959 - FACT (forerunner to COBOL)
1959 - COBOL
1959 - RPG
1962 - APL
1962 - Simula
1962 - SNOBOL
1963 - CPL (forerunner to C)
1964 - BASIC
1964 - PL/I
1967 - BCPL (forerunner to C)
1968-1979: establishing fundamental paradigms[edit]
The period from the late 1960s to the late 1970s brought a major flowering of programming languages. Most of the major language paradigms now in use were invented in this period:
Simula, invented in the late 1960s by Nygaard and Dahl as a superset of Algol 60, was the first language designed to support object-oriented programming.
C, an early systems programming language, was developed by Dennis Ritchie and Ken
Thompson at Bell Labs between 1969 and 1973.
Smalltalk (mid-1970s) provided a complete ground-up design of an object-oriented language.
Prolog, designed in 1972 by Colmerauer, Roussel, and Kowalski, was the first logic
programming language.
ML built a polymorphic type system (invented by Robin Milner in 1973) on top of Lisp,
pioneering statically typed functional programming languages.
Each of these languages spawned an entire family of descendants, and most modern languages count at least one of them in their ancestry.
The 1960s and 1970s also saw considerable debate over the merits of "structured programming", which essentially meant programming without the use of Goto. This debate was closely related to language design: some languages did not include GOTO, which forced structured programming on the programmer. Although the debate raged hotly at the time, nearly all programmers now
agree that, even in languages that provide GOTO, it is bad programming style to use it except in rare circumstances. As a result, later generations of language designers have found the structured programming debate tedious and even bewildering.
Some important languages that were developed in this period include:
1968 - Logo
1969 - B (forerunner to C)
1970 - Pascal
1970 - Forth
ignore subsequent bad blocks1972 - C
1972 - Smalltalk
1972 - Prolog
1973 - ML
1975 - Scheme
1978 - SQL (initially only a query language, later extended with programming constructs) The 1980s: consolidation, modules, performance[edit]
The 1980s were years of relative consolidation in imperative languages. Rather than inventing new paradigms, all of these movements elaborated upon the ideas invented in the previous decade. C++ combined object-oriented and systems programming. The United States government standardized Ada, a systems programming language intended for use by defense contractors. In Japan and elsewhere, vast sums were spent investigating so-called fifth-generation programming languages that incorporated logic programming constructs. The functional languages community moved to standardize ML and Lisp. Research in Miranda, a functional language with lazy evaluation, began to t
ake hold in this decade.
One important new trend in language design was an increased focus on programming for large-scale systems through the use of modules, or large-scale organizational units of code. Modula, Ada, and ML all developed notable module systems in the 1980s. Module systems were often wedded to generic programming constructs---generics being, in essence, parametrized modules (see also polymorphism in object-oriented programming).
Although major new paradigms for imperative programming languages did not appear, many researchers expanded on the ideas of prior languages and adapted them to new contexts. For example, the languages of the Argus and Emerald systems adapted object-oriented programming to distributed systems.
The 1980s also brought advances in programming language implementation. The RISC movement in computer architecture postulated that hardware should be designed for compilers rather than for human assembly programmers. Aided by processor speed improvements that enabled increasingly aggressive compilation techniques, the RISC movement sparked greater interest in compilation technology for high-level languages.
Language technology continued along these lines well into the 1990s.
Some important languages that were developed in this period include:
1980 - C++ (as C with classes, name changed in July 1983)
1983 - Ada
1984 - Common Lisp
1984 - MATLAB
1985 - Eiffel
1986 - Objective-C
1986 - Erlang
1987 - Perl
1988 - Tcl
1988 - Mathematica
1989 - FL (Backus);
The 1990s: the Internet age[edit]
The rapid growth of the Internet in the mid-1990s was the next major historic event in programming languages. By opening up a radically new platform for computer systems, the Internet created an opportunity for new languages to be adopted. In particular, the Java programming language rose to popularity because of its early integration with the Netscape Navigator web browser, and various scripting languages achieved widespread use in developing customized application for web servers. The 1990s saw no fundamental novelty in imperative languages, but much recombination and maturation of old ideas. This era began the spread of functional languages. A big driving philosophy was programmer productivity. Many "rapid application development" (RAD) languages emerged, which usually came with an IDE, garbage collection, and were descendants of older languages. All such languages were object-oriented. These included Object Pascal, Visual Basic, and Java. Java in particular received much attention. More radical and innovative than the RAD languages were the new scripting languages. These did not directly descend from other languages and featured new syn
taxes and more liberal incorporation of features. Many consider these scripting languages to be more productive than even the RAD languages, but often because of choices that make small programs simpler but large programs more difficult to write and maintain.[citation needed] Nevertheless, scripting languages came to be the most prominent ones used in connection with the Web.
Some important languages that were developed in this period include:
1990 - Haskell
1991 - Python
1991 - Visual Basic
1991 - HTML (Mark-up Language)
1993 - Ruby
1993 - Lua
1994 - CLOS (part of ANSI Common Lisp)
1995 - Java
1995 - Delphi (Object Pascal)
1995 - JavaScript
1995 - PHP
1996 - WebDNA
1997 - Rebol
1999 - D
Current trends[edit]
Programming language evolution continues, in both industry and research. Some of the current trends include:
Increasing support for functional programming in mainstream languages used commercially, including pure functional programming for making code easier to reason about and easier to paralleli
se (at both micro- and macro- levels)
Constructs to support concurrent and distributed programming.
Mechanisms for adding security and reliability verification to the language: extended static checking, information flow control, static thread safety.
Alternative mechanisms for modularity: mixins, delegates, aspects.
Component-oriented software development.
Metaprogramming, reflection or access to the abstract syntax tree
Increased emphasis on distribution and mobility.
Integration with databases, including XML and relational databases.
Support for Unicode so that source code (program text) is not restricted to those characters

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