Always we paid for a web hosting but can we get any chance to avail free web hosting?

Ofcource, there is lot of hosts who provides free web hosting services but the thing is that,are they really free?Some times this happens that they offer free web hosting but in place of free they charges for domain name,making banners etc.

At the same time these free web hosting provider get money through the making banners,pop ups and other kind of tools.They also includes some special kind of the tools in the tools manager in hope that we click that tool and avail the facility.