Complex sentence: The MARS-1 was capable of reserving seat positions, and was controlled by a transistor computer with a central processing unit consisting of a thousand transistors and a 400,000-bit magnetic drum memory unit to hold seating files.
Split into simpler sentences: The MARS-1 was capable of reserving seat positions. It was controlled a transistor computer, with a central processing unit consisting of a thousand transistors and a 400,000-bit magnetic drum memory unit to hold seating files.