What is 'classified advertisement website'?
I'm not a English native speaker, so it isn't familiar to my ears.
Do those sites connect buyers and sellers?
If I want to buy second-hand items on web, I can use them, right?
"Classified advertisement" means advertisements put under different
categories/classes/headings, like property, teaching jobs, IT jobs, loans, services, etc. So thaw website advertises things and services in different categories.