I have a few questions about politics. What is exactly is "congressional gridlock"?

My textbook does not give a outright definition of the term and left me confused. It stated ,

"The differences between the houses produce different perspectives. The views of senators will differ from the views of representatives. What we today refer to as “gridlock” is something to which the framers would not object. They feared quick action far more they they feared delay"

See? It’s telling very general and not in detail what it is. My homework depends on understanding congressional gridlock, explaining the causes, and what would I suggest to ‘break the gridlock’?