In building applications, an API simplifies programming by [[Abstraction (software engineering)|abstracting]] the underlying implementation and only exposing objects or actions the developer needs. While a graphical interface for an [[email client]] might provide a user with a button that performs all the steps for fetching and highlighting new emails, an API for file [[input/output]] might give the developer a [[Subroutine|function]] that copies a file from one ___location to another without requiring that the developer understand the [[Journaling file system|file system]] operations occurring behind the scenes.<ref name="Clarke4">{{cite web|last1=Clarke|first1=Steven|title=Measuring API Usability|url=http://www.drdobbs.com/windows/measuring-api-usability/184405654|website=Dr. Dobb's|accessdate=29 July 2016|date=2004}}</ref>
== History ==
Line 46:
===Operating systems===
An API can specify the interface between an application and the [[operating system]].<ref name="Oreilly91">{{cite book|last1=Lewine|first1=Donald A.|title=POSIX Programmer's Guide|date=1991|publisher=O'Reilly & Associates, Inc.|page=1|url=ftphttps://gammawww.sbininfostream.orgcc/pubmanaged-it-services-risk-assessment/doc/books/OReilly_-_POSIX_Programmers_Guide.pdf?Cl |accessdate=2 August 2016}}{{Dead link|date=November 2018 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> [[POSIX]], for example, specifies a set of common APIs that aim to enable an application written for a POSIX conformant operating system to be [[Compiler|compiled]] for another POSIX conformant operating system.
[[Linux]] and [[Berkeley Software Distribution]] are examples of operating systems that implement the POSIX APIs.<ref name="WestDedrick16">{{cite journal|last1=West|first1=Joel|last2=Dedrick|first2=Jason|title=Open source standardization: the rise of Linux in the network era|journal=Knowledge, Technology & Policy|date=2001|volume=14|issue=2|pages=88–112|url=http://www.joelwest.org/Papers/WestDedrick2001b.pdf|accessdate=2 August 2016}}</ref>
