what is meant by run line

[Roman]

Baseball's equivalent of the point spread is the runline. When placing a wager on the runline, the favourite is favored by -1.5 runs against the underdog by +1.5 runs. If you gamble on the favorites, your team must win by 2 runs and more. On the other hand, if you wager on the underdog with +1.5, your side could either succeed or fail by one run and your wager would still be paid out.