ATtiny microcontroller comparison chart
ATtiny (also known as TinyAVR) is a subfamily of the popular 8-bit AVR microcontrollers, which typically has fewer features, fewer I/O pins, and less memory than other AVR series chips. The first members of this family were released in 1999 by Atmel (later acquired by Microchip Technology in 2016).
Source: Wikipedia — ATtiny microcontroller comparison chart (CC BY-SA 4.0)