A transaction is when two parties in a suit mutually agree to end the suit. Typically, this happens when the two parties can reach a compromise outside of court.
In some states, transactions must be written formally. This provides a record of the transaction and helps to settle the matter formally.
Transactions can be mutually beneficial to the parties involved in a lawsuit. The reason is because going to trial and going through litigation can be very expensive. Doing so can cost a lot of money for each party. So, if the parties can reach some sort of compromise outside of court, then it can save both of them on legal fees or on other expenses associated with the trial. Once the transaction is finalized, then the lawsuit ends, and both parties can go about their business under the terms of the transaction.