How does a jet engine work?
A jet engine sucks air in, squeezes it, burns fuel in it, then blows the hot air out of the back. Blowing backwards pushes the plane forwards.
A jet engine sucks air in, squeezes it, burns fuel in it and blows the hot gas out of the back. Blowing backwards pushes the plane forwards.
Suck, squeeze, bang, blow
The fan and compressor pull air in and squeeze it. Fuel is sprayed into the squeezed air and burned, and the hot gas expands very fast. It spins the turbine, which drives the fan and the compressor, then rushes out of the back. The push forwards is called thrust.
The big fan
On most airliners the big fan at the front moves a huge amount of air around the outside of the engine. Most of the thrust comes from this air. It is quieter and uses less fuel than a plain jet.
Staying cool
The burning gas can be hotter than the melting point of the metal blades. Cool air flows through tiny holes in the blades to protect them.