Did you set it to open a specific page every time your opening firefox? Or Did you set it to open the last page you were on when you last log out? Check your "Options" >>> "General" Under General is your Start Up for your web browser When Firefox Start: You have 3 options to choose from 1) Show my home page 2) Show a blank page 3) Show my windows and tab from last time Home Page: This is set at this logo that looks like a House on your browser. If you haven't change it, may be your family member changed it. It should not be doing that on it's own, some one may have changed your settings. Stated above, these are the most common reasons why your browser is opening a certain page. Firefox is a great web browser, as well as Google Chrome. You may also set Firefox, Chrome or Internet Explorer as your default web browser. I personally never use Internet Explorer.