As your schematics grow in complexity, it isn’t always possible to draw simple connections between chips or devices.  Sometimes it isn’t possible to put two parts next to each other like a pin header and I/O chip meaning that wires have to run all over the schematic to make the connection.   That gets messy quick and not very easy to follow.

EAGLE automatically connects all nets (or wires) inside of a schematic when they have the same name.  This means even if they are not physically connected on the schematic giving them the same name will connect them together.  Using this trick, it is pretty easy to break up nets across the page.