When you open a new tab in your browser, you have a number of options. You can:
Type or paste an address into the Address bar to navigate to a new webpage.
Use any number of Accelerators, which enable you to select text and use it to do such things as opening a street address in a mapping website or looking up the dictionary definition of a word.
Turn on InPrivate Browsing, which enables you to surf the web without leaving a trace by automatically clearing your website history when you close the browser window.
Reopen tabs you have previously closed, either in your current browser session or in a previous one.
Here are some links to more detailed information on these options:
Tabbed browsing: frequently asked questions
Using Accelerators to find addresses, define words, and do other tasks with selected text
What is InPrivate Browsing?
Open tabs you've previously closed