I'm a bit confused with what the word invention means in this context. Does it mean truly inventing some new algorithm (not in Knuth) as a normal part of your w

I'm a bit confused with what the word invention means in this context. Does it mean truly inventing some new algorithm (not in Knuth) as a normal part of your work. Or does it mean just writing new code from scratch rather thanh using a library? I've written a lot of code in my career (and as a hobby), but I doubt that I've truly invented something new.