What is the difference between pipe cleaner, primer / cleaner and primer?

All pipe surfaces should be thoroughly cleaned with pipe cleaner. The cleaner is formulated to remove surface dirt and any oil or grease that exists on the pipe from the manufacturing process. Primer/cleaner and primer contain more aggressive solvents and will soften the pipe surface to allow the solvent cement to penetrate more effectively. Primer is often required by plumbing code and sometimes a purple colored primer (purple primer) is needed.