Do you get overwhelmed by the number of windows you open up in your web browser? Using tabs can keep things more manageable.
Of all of the changes web browsers have gone through over the years, I think the addition of tabs is the one I appreciate most. They allow me to use one window to flip easily between multiple web pages. I also love that the interface for working with tabs is so similar across all the different web browsers I use.
To use tabs in a browser:
Instead of using File→New Window or Ctrl-N (Cmd-N on a Mac) to open up a new window, use Ctrl-T (Cmd-T on a Mac) to open a new tab. Or, click on the "+" sign next to your current tab.
This opens up a blank tab, and you can use it to navigate to the page you want to view.
You can open up many tabs in a single window, and easily navigate between them by clicking on a tab to bring it to the front.
You can get rid of a tab you're finished with by clicking on the "X" in its title.