Internet Explorer (IE7,8,9)
Click the button in the bottom-right corner (next to where it says 100%) and select the desired zoom percentage.
or, hold the Ctrl key down and move your mouse wheel.

There is also an option to ignore the font sizes specified by the page author:
1. Select menu item Tools / Internet Options;
2. Select the "General" tab;
3. Press the "Accessibility" button;
4. Tick the option "ignore font sizes specified on webpages"
5. Press the "OK" button;
6. Press the "OK" button.

Firefox
- Zoom in and out by holding the Ctrl key down and moving the mouse wheel
- or Zoom the text size in and out by using Ctrl & '+' and Ctrl & '-'
- or Set the font size in menu Tools / Options.

Google Chrome
- Zoom in and out by holding the Ctrl key down and moving the mouse wheel
- or Click on the spanner button to the right of the address bar, and this opens a menu which includes a zoom option