keeping timesche dul ing ta sksand aunching progr ams running programs while you're sitting at your computer is finebut it' also useful to have programs run without your direct supervision your computer' clock can schedule programs to run code at some specified time and date or at regular intervals for exampleyour program could scrape website every hour to check for changes or do cpu-intensive task at am while you sleep python' time and datetime modules provide these functions you can also write programs that launch other programs on schedule by using the subprocess and threading modules oftenthe fastest way to program is to take advantage of applications that other people have already written