In the house, there are a lot more people therefore it is required that more people agree on a bill. In the house, there is a speaker of the house. In the senate, i believe the vice president is the senate's version of the speaker. In which he decides the final vote if the vote is even. A similarity is that if a bill starts in the senate and receives the 2/3 vote, it must go to the house to get voted on as well and vise versa. Also, all bills that receive the 2/3 vote in both the senate and the house, all must go to the president to get either vetoed or passed. Hope this helps!
