http://www.teachenglishinasia.net/korean-verb-ending-database you will find good info about basic Korean verb-endings including the reason why it is used so often.

ㅂ니다 is a formal ending. It's not used among people who have close & friendly relationship with each other. We use -요 in fact.

"입니다"means "be"(is ,are,was,were ),it's a grammar,so we can see it used in many sentence~~

"입니다." ===> is