What is busy waiting in context of operating system?

Answer 1

Busy waiting is where a process checks repeatedly for a condition- it is "waiting" for the condition, but it is "busy" checking for it. This will make the process eat CPU (usually).

For example:

function stay_running_until_there_is_internet() {    
    while(check_internet() == 0) {    
        \\ wait    
    }    
}