[Gmail-Users] Re: Folders to Place Emails Into

Labels are kind of like folders, what they do is add a little tag to messages.  When you click on the label name, Gmail does a search for the tag assigned to that label and shows you all messages with that tag or label.  What makes labels different from folders is that one message can have many labels. 

To set up a label, click Settings > Labels > Create new label

From there, you want to find all the messages you want to be assigned to that label and click the drop down menu More Actions > Apply Label: Label Name

You can also have Gmail automatically assign labels to incoming mail by creating a filter.

Well, I hope this helps.