How useful are all those algorithms at work?

[MisterWhite]

Since i have no experience on what kind of work is done in IT companies (just finished school, will start bachelor's) I start to wonder if algorithms like (KMP, BST, greedy, Graham Scan, knapsack) were of any use in real world work? (Those were just some that i've encountered in exercises)

[Nuluvius]

It really helps to understand them such that you appreciate the ramification of their use in a particular context. However unless you are doing something quite specialised or niche then you'll likely just be using existing types, structures and libraries that make use of them 'under the hood'.

[espurritado]

they are really useful. Basically, they are the difference between a program taking for ever to do something and finishing in an acceptable time frame