Life cycle of pipeline execution

I am new in Circle CI but I think that is a easier tool than others. I would like something about cache, and about the docker images. This questions are related to life cycle of pipeline.
I guess the life cycle is:

  • Build docker image
  • Run commands or similar
  • Execute steps
  • Destroy docker images

I want to know if these descriptions are correct, and I would like to know if I can use cache of last pipelines.
I want to say:

  1. Pipeline n1 run
  2. Pipeline n2 running with cache of Pipeline 1