APA may refer to:
An apartment (American English), flat (British English) or unit (Australian English) is a self-contained housing unit (a type of residential real estate) that occupies only part of a building, correctly, on a single level without a stair.
Apache Hadoop (pronunciation: /həˈduːp/) is an open-source software framework used for distributed storage and processing of big data sets using the MapReduce programming model.
The Apache (/əˈpætʃiː/; French: [a.paʃ]) are culturally related Native American tribes from the Southwestern United States, and have traditionally lived in Eastern Arizona, Northern Mexico (Sonora and Chihuahua), New Mexico, West Texas, and Southern Colorado.
Apache Subversion (often abbreviated SVN, after its command name svn) is a software versioning and revision control system distributed as open source under the Apache License.
The Apache HTTP Server, colloquially called Apache (/əˈpætʃiː/ ə-PA-chee), is the world's most used web server software.
Apache OpenOffice (AOO) is an open-source office productivity software suite. It is one of the successor projects of OpenOffice.org and the designated successor of IBM Lotus Symphony.