Explanation

The main electronic component used in first-generation counterparts was Vacuum Tubes and Valves.

Leo is called the first-generation computer.

The five generations of computers:

1. First Generation (1946-1959 or 1940-1956): Vacuum tube-based technology (e.g., ENIAC).
2. Second Generation (1959-1965 or 1956-1963): Transistor-based technology.
3. Third Generation (1965-1971 or 1964-1971): Integrated circuit-based technology.
4. Fourth Generation (1972-1980): VLSI microprocessor-based technology.
5. Fifth Generation (1980-present): ULSI microprocessor-based technology, with a focus on artificial intelligence.