I'm assuming you're talking about when ordering from someone online.
Normally if you purchase a table online, the table is shipped directly to your house and you're responsible for getting it inside and checking it for shipping damage. With "White Glove" the table will be shipped to the installer directly. They will be responsible for making sure everything required was shipped properly and wasn't damaged. They will then bring it to your house and do the installation so you don't have to do a thing.
If you are thinking about buying a table online, I'd check with the folks on here to make sure they don't steal your money...
Brian