Clipper is a computer programming language that is used to create software programs that originally operated primarily under DOS. Although it is a powerful general-purpose programming language, it was used to create primarily database/business programs.

Clipper was originally created as a compiler for the (then) very popular dBASE III language. Compiling changes dBASE code from interpreted code , which must be interpreted every time each line of code is executed, to P-Code (or pseudo-code), which uses a Virtual Machine to process the compiled P-Code. P-Code is considerably faster, but still not as fast as the machine code generated by native compilers. Clipper was created by a company named Nantucket, and later sold to Computer Associates.

As the product matured, it remained a DOS tool for many years, but added elements of the C programming language and Pascal programming language, as well as OOP, and the unique code-block data-type (hybridizing the concepts of dBase macros, or string-evaluation, and function pointers), to become far more powerful than the original. Nantucket's Aspen project later matured into the Window's native-code compiler Visual Objects.

As of 2005, the Clipper language is being actively implemented, and extended, by multiple organizations/vendors, free (GPL based) like Clip, xHarbour, as well as commercial compilers like Xbase++, FlagShip.

Many of the current (2005) implementation are portable (DOS, windows, Linux (32,64), Unix (32,64), OS/X) and support many langauge syntax extensions, and greatly extended Run-Time librarries, as well as various Replaceable Database Drivers (RDD) supporting many popular database formats, like DBF, DBTNTX, DBFCDX (FoxPro, and Comix), MachSix (Apollo), SQL, and more, all compatible with the standard dBase/xBase syntax, while also offering OOP approaches, as well as target based syntax such as SQLExecute( ... ), etc..

Clip is a multi-platform (both linux and windows(cygwin)) variant with many additional features and libraries(for gtk, fivewin, netto, mysql, odbc, cti, tcp, gzip, interbase, oracle, postgres), which is quite fast, has support for hiper-six and foxpro RDD's, and can compile existing clipper source code with very minor changes.

xHarbour is a free (GPL + exception supporting Commercial applications) multi platform (DOS, Windows, Linux (32,64), Unix (32,64), OS/X) extended Clipper compiler, offering multiple GT (Graphic Terminals), including Console drivers, as well GUI's (free such as HWGui , MiniGUI and commercial, such as Visual xHarbour, FiveWin, and many more), as well as Hybrid Console/GUIs, like GTWvt , and GTWvw . xHarbour is 100% Clipper backward compatible, which supports many langauge syntax extensions, greatly extended Run-Time librarries like OLE, ODBC, MySql , Postgress , TIp , TXml , RegEx , HbZip xbScript and exetensive 3rd. party support. xHarbour is also available available as a commercial ditribution from xHarbour.com Inc..