The best example for compression is to use slap for the example. When you slap and pop, you get some extreme lows and highs naturally. When you use compression, you set a threshold for the range you wish to keep the highs and lows.
This is similar, well, the same thing as dynamic compression on your tv or home audio. So when watching a show, where people re whispering, you would turn up the volume to hear it, but then when an explosion, or gunshots, or someone screams, you ave to turn the tv back down, but if you use your dynamic compression, it increases the volume of the whispers to an audible level, and decreases the level of the explosion to a Leo that doesnāt blow your ears out, or wake up the person sleeping in the next room.
Compression evens out your playing. Your slaps can be quieter then your pops, and if you turn up the volume to hear your slaps, the pos can be to loud, piercing thru, and can be overpowering.
With compression on, the slaps are udible and your pops are toned down a bit.
This is the same with the rest of your plying.
Now some compression pedals are ālimitersā like that, and enhancers together, they limit the highs, and enhance the lows.
Other compressors work more like a 3band EQ and offer overdrive and sustain.
There are really a lot of options. The zoom does a good job of offering the best out of the different types to play with, or use in different environments.
The Limiter/ Enhancer is all around my top choice for compression, if it were the only co pression pedal I were to have, but the others can be great too. Some people will have a compression at each end of the chain. I have not been able to do this yet, buwill when I get the multi stomp.
One thing to keep in mind, compression pedals can be noisy when not playing, so you can use noise gates (built in the zoom) or tweak them to not be.
There is a lot more about compression, and way more choices then I can begin to touch here.
There are good YT videos explaining compression, and many comparison videos as well that are good to way.
You could probably have a whole forum dedicated to compression, if there is not one already.
HTH and was clear, I think I jumped around a bit at the beginning