A fake is a 'local' or lower fidelity implementation of the real thing. A array/memory backed DB instead of postgres, etc. A mock is a cache for a desired retu

A fake is a 'local' or lower fidelity implementation of the real thing. A array/memory backed DB instead of postgres, etc. A mock is a cache for a desired return value (which is hopefully what the real interface would correctly return). Edit: actually sethammons link is great