The ATmega88 is an electronic integrated circuit microcontroller produced by the Atmel corporation. It has the basic Atmel AVR instruction set. One of the packaging configurations is the dual in-line package (DIP). It has 23 I/O pins and operates at up to 20 MHz for clock speed. It has an 8-bit core and 8K flash (program) memory.
Many of Atmel's microcontrollers in this line have similar instruction sets, so if an engineer learns the instruction set from one of their microprocessors, this knowledge is transferable to other microcontrollers in the line.
References
ATmega88 Wikipedia(Text) CC BY-SA