To split the screen on a Mac and use two apps side by side, you can use the built-in Split View feature by following these steps:

1. Open the two apps or windows you want to use simultaneously.
2. Hover your pointer over the green full-screen button in the top-left corner of the first app’s window.
3. When the menu appears, select either “Tile Window to Left of Screen” or “Tile Window to Right of Screen” depending on which side you want that app to occupy.
4. On the other side of the screen, click the other app or window you want to use. This will fill the other half of the screen and create the Split View.

Once in Split View, you can adjust the size of each window by dragging the vertical divider bar between them. You can also switch sides by dragging a window’s title bar to the other side or replace one app with another by hovering over the green button and choosing “Replace Tiled Window”

. To exit Split View, move your cursor to the top of the screen to reveal the window buttons and click the green button on either app to return it to normal window mode

. Alternatively, you can enter Split View via Mission Control by opening both apps in full screen, swiping up with three or four fingers to open Mission Control, then dragging one app’s window onto the other in the Spaces bar at the top of the screen and selecting a side

. This feature requires macOS El Capitan (10.11) or later