There are 4 lists what to each of them do?

[gohanrage]

Add to Watch List, Add to Gift Ideas, Add to Research,  Add to Wish List

When ever I am going to buy something I see that there is a drop down menu which says add to list. I have no idea what all these lists do. I typically add an item to all four but I have no idea the difference of each of them. 

[momcqueen]

I think it's merely a mechanism for which users can organize their lists to make items easier to find later, like putting things into particular folders on a desktop instead of a pile. I don't think ebay keeps track of who's putting what into where, other than for retrieval purposes.

[patken123]

I put them all in my wish list ,easier to remember.