The two Houses communicate their decisions to one another by sending a ‘Message’. Messages are carried by Clerks from one Chamber to the other. The arrival of a Message from the Lords does not disrupt what’s going on in the Commons Chamber, but it will be recorded in the minutes for that day.
Messages are mostly used to communicate decisions about legislation. These can be simple, for example one House telling the other that it has passed a bill or that it agrees to changes made by the other House. But they can be more complex, for example if they need to communicate disagreements, alternative suggestions or amendments to Lords Amendments.