You must have spotted at least one commercial or military aircraft once in your lifetime (I guess) but have your ever wondered how does it moves with such ridiculous speeds ?
Your answer to me would be the engines (the engines makes the aircraft to move), yeah you are correct but I am talking about it's simple working principal, so let's get started.
I would be mainly talking about the working of an civil aviation aircrafts, because all of them are simply based on same working principle....
So starting from scratch, the force which makes the aircraft to move forward is called thrust (simple defined as the sudden change in velocity or in more simplified terms a violent force which makes things to move in a particular direction).
So first let's visualize a commercial jet engine....
The best labelled picture I could found on Internet
3D-View for better understanding
So let's start what these massive blades do is they suck or pump air inside and then the compressor (made up of many blades connected to the shaft) comes into action and raises the pressure of the inlet air, and then high speed rotating blades flush and squeeze the air and this air is sprayed with jet fuel and then the electric sparks lights up the mixture , and now what ? there is a sudden expansion due to this the air blasts out through the nozzle, providing and instant thrust to the aircraft, and while going out of the nozzles this air also passes with another set of turbines which are connected to the same shaft as the compressor.
So it's a simple concept, now I guess after reading this bit of information you can try to answer these interesting question ( just for curiosity),
Can you observe and answer most of the commercial engines which you see are in the shape that goes wide (at entry) and narrow (at exist) ?
Have you heard of maximum ceilings (the maximum altitudes at which planes can fly) so can you answer why such kinds of max caps exist ?
Now just for facts,
World's most powerful commercial jet engine was recently built and tested by General Electric named as GE 9X which are being built exclusively for Boeing 777x ( A long-haul widebody commercial jet), it was a GUINNESS WORLD RECORDS which produced 134,300 pounds of thrust !!!
That's incredible I guess....
In ending note, I would like to include a open source video by Pratt & Whitney (A leader in Engine Manufacturing including other such as Rolls Royce , General Electric) on working of commercial jet engines.