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Free-form language
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<p>In <a href="/facts/Computer_programming/QmSsFnu0">computer programming</a>, a free-form language is a <a href="/facts/Programming_language/cWTYbgWa">programming language</a> in which the positioning of <a href="/facts/Character_(computing)/X2zKLFFB">characters</a> on the page in program text is insignificant. Program text does not need to be placed in specific columns as on old <a href="/facts/Punched_card/44WsPulQ">punched card</a> systems, and frequently ends of lines are insignificant. <a href="/facts/Whitespace_character/Q5xRIaSz">Whitespace characters</a> are used only to delimit <a href="/facts/Token_(parser)/T1JYWpIf">tokens</a>, and have no other significance. Free-form languages allow a greater degree of flexibility and have fewer syntactic rules to learn, which could lower the entry barrier for beginners. </p><p>Most free-form languages descend from <a href="/facts/ALGOL/wlFJGNEx">ALGOL</a>, including <a href="/facts/C_(programming_language)/Ky2No763">C</a>, <a href="/facts/Pascal_(programming_language)/b3yvp8bF">Pascal</a>, and <a href="/facts/Perl/fx31kjlT">Perl</a>. <a href="/facts/Lisp_(programming_language)/xJHA3CrX">Lisp</a> languages are free-form, although they do not descend from ALGOL. <a href="/facts/Rexx/hAzh6FeR">Rexx</a> and its dialects <a href="/facts/Object_REXX/E7CoEr7D">ooRexx</a> and <a href="/facts/NetRexx/109heq3w">NetRexx</a> are mostly free-form, though in some cases whitespace characters are <a href="/facts/Concatenation/1npYg6rc">concatenation</a> operators. <a href="/facts/SQL/UjQLJcYm">SQL</a>, though not a full programming language, is also free-form. </p><p>Most free-form languages are also <a href="/facts/Structured_programming/zA8b8dP1">structured programming</a> languages, which is sometimes thought to go along with the free-form syntax: Earlier <a href="/facts/Imperative_programming/6b5dUnE1">imperative programming</a> languages such as <a href="/facts/Fortran_77/m1KqjcMU">Fortran 77</a> used particular columns for line numbers, which many structured languages do not use or need. </p><p>Structured languages exist which are not free-form, such as <a href="/facts/ABC_(programming_language)/lgYVS5y4">ABC</a>, <a href="/facts/Curry_(programming_language)/hDqY8NIf">Curry</a>, <a href="/facts/Haskell_(programming_language)/4Htv9WLu">Haskell</a>, <a href="/facts/Python_(programming_language)/YbuGqofa">Python</a> and others. Many of these use some variant of the <a href="/facts/Off-side_rule/LmengNTS">off-side rule</a>, in which indentation, rather than keywords or braces, is used to group blocks of code. </p>