A high-bypass turbofan running live in your browser. Nothing here is video. Scroll to move through the engine stage by stage, drag to look around it, switch the systems on and off. There is a short test at the end.
Air enters at the fan and leaves at the nozzle. Most of it never reaches the fire, and that is the whole trick of a modern engine. The air that does reach the fire is squeezed, burned, and used to drive the very compressor that squeezed it.
Eighteen blades, a little over five metres across. Most of what you feel as thrust starts here, and most of the air it moves goes straight past the core without ever being burned. In a modern high-bypass engine that bypass air accounts for the large majority of total thrust.
The squeeze begins. Watch the core narrow as you move back: compression is geometry you can see, not a number on a chart. Also called the booster, it sits on the same shaft as the fan.
The narrowest point in the whole engine. By the time air leaves here it is several hundred degrees hot from pressure alone, before a drop of fuel has been added. Squeezing a gas heats it, and that is why the compressor is the hottest thing in the engine that is not on fire.
The only place fuel burns, and far smaller than you would expect for the machine wrapped around it. This one is can-annular: a ring of discrete cans rather than one continuous chamber, each perforated so cooling air can film the inside of the liner.
Expansion starts doing work. These blades drive the compressor that squeezed the air in the first place, which is why the back of the engine and the front are really the same machine. Gas leaving here is cooler than at the combustor, because the turbine has taken energy out of it.
The radius opens back out and the loop closes: this stage drives the fan at the very front, through a shaft running the whole length of the engine. The bands around the blade tips are shrouds, which seal against the casing and damp vibration.
Everything below is answered somewhere above. Scroll back up and look at the engine if you need to.
Every stage is separately addressable, which is the part that matters for training and sales material. A render shows someone a machine. This lets them take it apart and then proves they followed it, which is the difference between watching and understanding.