For PCs:

Explorer -
To change text size in later versions of the Explorer browser you need to set Accessability in your Internet Options:
- Under Tools in your top menu bar select Internet Options
- Select the Accessibility tab
- Check Ignore font sizes specified in web pages
Then:
- Under View in topmenu bar select increase or decrease text size

Netscape-
Hold down CTL (control key) and click on ] to increase size
CTL and [ to decrease size

For Apple Macs:

Explorer -
Hold down Apple key and press + to increase size
Apple and press - to decrease size

Netscape-
Hold down Apple and Shift keys and click on ] to increase size
Apple/Shift and [ to decrease size