Editing Programming language (section)

====Commonly supported types====
{{See also|Primitive data type}}
Early programming languages often supported only built-in, numeric types such as the [[integer]] (signed and unsigned) and [[floating point]] (to support operations on [[real number]]s that are not integers). Most programming languages support multiple sizes of floats (often called [[Single-precision floating-point format|float]] and [[Double-precision floating-point format|double]]) and integers depending on the size and precision required by the programmer. Storing an integer in a type that is too small to represent it leads to [[integer overflow]]. The most common way of representing negative numbers with signed types is [[twos complement]], although [[ones complement]] is also used.{{sfn|Sebesta|2012|pp=246–247}} Other common types include [[Boolean data type|Boolean]]—which is either true or false—and [[Character (computing) |character]]—traditionally one [[byte]], sufficient to represent all [[ASCII]] characters.{{sfn|Sebesta|2012|p=249}} 

[[array (data type)|Arrays]] are a data type whose elements, in many languages, must consist of a single type of fixed length. Other languages define arrays as references to data stored elsewhere and support elements of varying types.{{sfn|Sebesta|2012|p=260}} Depending on the programming language, sequences of multiple characters, called [[string (computing)|strings]], may be supported as arrays of characters or their own [[primitive type]].{{sfn|Sebesta|2012|p=250}} Strings may be of fixed or variable length, which enables greater flexibility at the cost of increased storage space and more complexity.{{sfn|Sebesta|2012|p=254}} Other data types that may be supported include [[list (computing)|lists]],{{sfn|Sebesta|2012|pp=281–282}} [[associative arrays|associative (unordered) arrays]] accessed via keys,{{sfn|Sebesta|2012|pp=272–273}} [[record (computer science)|record]]s in which data is mapped to names in an ordered structure,{{sfn|Sebesta|2012|pp=276–277}} and [[tuple]]s—similar to records but without names for data fields.{{sfn|Sebesta|2012|p=280}} [[Pointer (computer programming)|Pointer]]s store memory addresses, typically referencing locations on the [[Heap (programming)|heap]] where other data is stored.{{sfn|Sebesta|2012|pp=289–290}}

The simplest [[user-defined type]] is an [[Ordinal data type|ordinal type]], often called an [[enumeration]], whose values can be mapped onto the set of positive integers.{{sfn|Sebesta|2012|p=255}} Since the mid-1980s, most programming languages also support [[abstract data types]], in which the representation of the data and operations are [[information hiding|hidden from the user]], who can only access an [[Interface (computing)|interface]].{{sfn|Sebesta|2012|pp=244–245}} The benefits of [[data abstraction]] can include increased reliability, reduced complexity, less potential for [[name collision]], and allowing the underlying [[data structure]] to be changed without the client needing to alter its code.{{sfn|Sebesta|2012|p=477}}