A hostel is usually accommodation with shared rooms and bathrooms, quite often bunk beds so it is therefore very economical to stay in such a place. Typically young people travelling would stay in hostels. Quite often hotels may have a very good "social scene" too. Whereas hotels are more expensive but the rooms are private and usually you have your own bathroom too. Hope that helps!

No, hostels are like dormitories, they provide cheaper accommodation compared to hotels. Hostels have only provides the basic essentials i.e. the bed, shower (no towels), etc. Mostly for students, workers, travelers. Whereas hotels, we all know, its bigger, more comfortable and provides more services.

Can ....instead of could