A microprocessor from Motorola. It was the successor to the Motorola 68010 and was followed by the Motorola 68030. The 68020 has 32-bit internal and external data and address buses and a 256-byte instruction buffer, arranged as 64 direct-mapped 4-byte entries[?].
The 68020 added many improvements to the 68010 including a 32-bit ALU and external data bus and address bus, and new instrucitons and addressing modes. The 68020 (and 68030) had a proper three-stage pipeline.
The new instructions included some minor improvements and extensions to the supervisor state, some support for high-level languages which didn't get used much (and was removed from future 680x0 processors[?]), bigger (32 x 32-bit) multiply and divide instructions, and bit field manipulations.