When was the first computer invented?

The first mechanical computer was developed in the early 19th century by Charles Babbage, an English engineer, and Ada Lovelace, a mathematician. At the computer’s core was the Difference Engine, which was responsible for making calculations using multiple sets of numbers printing the outputs.
The first digital computer was the Atanasoff-Berry Computer (ABC). The ABC was developed in 1942 by Iowa State University professor John Vincent Atanasoff and graduate student Cliff Berry. This computer used vacuum tubes to make binary computations and processed Boolean logic. However, the ABC lacked a CPU and was, therefore, not programmable. Subsequent computer evolutions added programming capabilities, RAM, transister,microprocesser  and portability as key characteristics.

What are the types of computers?