Pre spray vs pre wash
Often used interchangeably a pre wash and a pre spray are quite different.
A pre wash, as explained by a lot of our guides is a process, where you spray the car with a pre wash chemical and then let it dwell and rinse it off.
That rinse removes a lot of contaminants and the dwell allows for a good breakdown of grime.
A Pre Spray is mostly used during rinseless washes, but if you enjoy it, it can also be done post pre wash on a regular wash. Pre Spray means, that you put a pre spray chemical on the car, often the rinseless wash itself, tho some acidic or alkaline pre spray chemicals are emerging, and then wash over it with the soap/rinseless wash in your bucket. This helps with dissolving grime but does not add the safety of the rinse, so that contaminants are loosened but not removed from the paint, so they keep being a scratch risk.
A good method if you do a full rinseless, however any method that uses at least one Rinse before the contact wash (even if the contact wash itself is rinseless) is superior.
Here are some more in depth guides:
https://howtoautodetail.com/docs/detailing-guides/exterior/pre-wash-guide/
https://howtoautodetail.com/docs/detailing-guides/exterior/rinseless-washing/