What is the point of making a background layer go transparent and renaming it in Photoshop?

Question

I've seen this convention a lot but I don't really understand the use for it - or for a solid background layer at all, to be honest. I'd be very grateful if someone could explain why each new project starts out with a solid background layer, which most people then convert to transparency?

Thank you very much in advance.

Answer 1

Each new project doesn't have to "start out with a solid background."

When you choose File > New you have a choice of what the background can be....

If you change your Background Contents in the new file dialog, it will stay set that way until you change it again.