Question

alan turing: 1. time period: 2. what did the term computer mean? 3. main contribution:

Explanation:

1. Alan Turing lived from 1912 - 1954, a mid - 20th century figure.
2. In Turing's time, "computer" originally referred to a person who performed numerical calculations by hand.
3. Turing's main contributions include the Turing machine concept, fundamental to theoretical computer science, and his work on code - breaking during World War II, especially at Bletchley Park.

Answer:

1. Mid - 20th century (1912 - 1954).
2. A person who did numerical calculations by hand.
3. Turing machine concept and code - breaking work in World War II.