Okay kiddo, imagine you have a cookie and you want to share it with your friend. You hold the cookie out to your friend and say "Do you want to trade something for this cookie?"
That's kind of like an "invitation to treat". It's not a formal offer to sell the cookie, but it's the start of a negotiation.
Basically, an "invitation to treat" is when someone makes an offer or suggests they are willing to make an offer, but they haven't actually made the offer yet. It's like they're testing the waters to see if someone is interested in what they have to offer.
For example, when you see a sign in a store window that says "Sale: all items 50% off!", that's not actually an offer to sell anything at a discount. It's an invitation to treat. The store owner is letting people know that they're willing to sell things at a discount, but they haven't officially made an offer yet.
So, an "invitation to treat" is basically like a little invitation to start talking about a potential deal. It's not legally binding, but it's an important part of the negotiation process!