Each memory cell is some number of bytes . A byte is the amount of storage required to store one character, i.e. 'S'. Bytes are composed of smaller units called bits . Bits are binary digits, and can be either 0 or 1. Storing means placing some information in a memory location.
Loading means reading information from a memory location.
Input devices allow us to enter data into the computer. System software Stored program concept - John Von Neumann. Program resides in the computer rather than on tape, punchcards, etc. System software - tools to facilitate using the system. Operating system - collection of these tools that manage and abstract system resources.