Un coprocessore può non essere un processore di utilizzo generale: ad esempio, alcuni coprocessori non possono eseguire istruzioni in memoria, eseguire istruzioni di controllo del flusso del programma oppure operazioni di input/output, gestire la memoria. Questi chip richiedono che il processore processi le loro istruzioni e gestisca tutte le operazioni legate alle funzioni che essi devono svolgere. In alcune architetture il coprocessore è più un computer di uso generale ma impostato per svolgere solo alcune limitate funzioni sotto il controllo diretto di processore che ne supervisiona i compiti.
Coprocessors for floating-point arithmetic became common in desktop computers throughout the 1980s and into the early 1990s. Early 8-bit and 16-bit processors used software to carry out [[floating-point]] arithmetic operations (though some modern processors on unusual architectures still employ this technique). Where a hardware ''math co-processor'' was supported by the computer hardware and software, floating-point calculations could be carried out many times faster. Math co-processors were popular purchases for users of [[computer-aided design]] (CAD) software and scientific and engineering calculations. Early floating-point units, such as the [[AMD 9511]], Intel [[I8231]] and [[Weitek]] FPUs were treated as peripheral devices, whilst later units, such as the [[Intel 8087]], [[Motorola 68881]] and [[National 32081]] were more closely integrated with the CPU.
Another form of co-processor that became common during this era were the simple Video Display coprocessors, as used in the [[Atari 8-bit family]], the [[Texas Instruments TI-99/4A]] and [[MSX]] home-computers, which were called "[[Video Display Controller]]s". The [[graphics processor]] chip in the Commodore [[Amiga]] series was known as the "[[Original_Amiga_chipset#Copper|Copper]]".
As microprocessors developed, the cost of integrating the floating point arithmetic functions into the processor declined. High processor speeds also made a closely-integrated coprocessor difficult to implement. Mathematics co-processors are now uncommon in desktop computers. The demand for a dedicated graphics co-processor has grown, however, particularly due to an increasing demand for realistic 3D graphics in computer games.
[[Image:Intel 8087 arch.svg|right|thumb|i8087 and i80287 microarchitecture.]]