A revolver is a line of credit that companies use for financing. You can think of it almost like a credit card for a company — they make some general purpose ag

A revolver is a line of credit that companies use for financing. You can think of it almost like a credit card for a company — they make some general purpose agreement with a bank for $X of credit at y% interest, and can use that at their discretion. Companies generally raise debt through specific bond offerings, so this is just a quicker way for them to tap capital instead of going to market each time.