What is Serialism?

Serialism is the use of all 12 notes in a musical phrase - there are a limited amount of variations possible. This one I made up - and I'm quite confident it's new (never before conceived). I could be wrong - I think it's 7/8 timing, giving it a polyrhythmic sound.
This phrase has some harmony - but more dissonance (which is typical for serialism).
Here is an autodidact & amateur freestyle example: