Difference between multiprogramming and uniprogramming

What is uniprogramming Uniprogramming means one program sits in main memory at a time. Uniprogramming was used in old computers and mobiles. When the computer starts then operating system and application programs are loaded into main memory. We only count user programs running in RAM. RAM is also called main memory. In old operating systems (OS) only one program runs on the computer at a time. Either of [...]