That depends on what you're doing, and what sound you want. If you're making a beat and you do something like put a Maximiser or a limiter on the "Master" track, then you technically are using "Compression" If you are an engineer you most certainly will use compression all the time. There are producers I know that compress there beats using 2 different compressors on the master channel. There are producers I know that use compressors on certain individual tracks. Then I know producers who don't mix there track at all and just level everything.
It's a mixed bag and really depends on what you are going for.
I noticed that leveling cleans things up enough to where I only need light eq'ing. I used to try to eq everything and wonder why things sounded bad in the end. I go through some old files and I was doing all kinds of cutting and boosting of frequencies for no reason.