House committees are busy preparing reconciliation bills that can skate through Congress. This round, the goal is to get a $1.9 trillion COVID-19 relief package to President Joe Biden’s desk.

Budget reconciliation is a parliamentary tool that would allow the package to pass in the Senate with just a simple majority, bypassing that chamber’s usual 60-vote threshold to end debate.

But how does this process work, and why can Congress do it at all? Watch as we explain.

[Read more: The cooling saucer and other Senate hooey]