The layout shows where the text, photos, advertisements etc.. should appear on the page. Almost all newspapers use computers to create layouts. Usually these layouts are just empty frames that are filled when the news comes in.
Every day newspapers must be finished at a certain time, so that they can be delivered to the readers on time. For the morning editions this deadline is mostly late at night or shortly after midnight. For newspapers published in the afternoon the deadline is sometime in the morning or near noon.