Writing for your web site is not the same as offline writing. The fonts used for print media are different than web fonts. This is because it's harder to read text on a computer screen and visitors tend to scan your web pages rather than read them word for word. When deciding on what web font to use, take into consideration the character of your site and whether the web font type is widely available (accomodates different screens and operating systems).

If you use the wrong web font, your web pages will may appear unprofessional and you may lose visitors to your competition.

So how do you decide on what web site font to use?

1. Analyze the character of your web site - for most web sites you would use a large or fancy font for your header to capture your visitors attention and a smaller web font for body text. When using a fancy font make sure it is available on most computers otherwise your visitors won't be able to read it. (To get around this, read my article "Improve your web site design with a fancy font" http://www.isitebuild.com/fancyfont.htm).

2. Search engine compatibility - fonts used within images can be seen on all computers, however it can't be read by the search engines. They can only "read" text. When designing images always use the "alt" tag to convey what your image is about. Try to include appropriate keywords in your web site copy. This will help the search engines index your site.

3. Use a web safe font - there are 2 types of fonts that are widely used:

Serif Fonts - these are most widely used for PRINT media ie Times Roman, Georgia, but are not good for the Web, because they are difficult to read on the screen. Serif fonts are those that have fine cross-lines at the extremities of the letter.

Sans Serif Fonts - these are fonts that don't have serifs. They are the best fonts to use for the WEB (ie Verdana, Arial, Helvetica, Trebuchet) but are not appropriate for print media.

Here's a great readability study that was done when comparing serif and sans serif fonts: http://www.wilsonweb.com/wmt6/html-email-fonts.htm

4. Use the correct font size - alternative font sizes add flavor and character to your web site. If you want your text to be viewed correctly for both PC and MAC users, then it's better to use pixels rather then points. Points may look all right on a PC but will appear smaller on a MAC (although these days there are only a small percentage of folks that use MACs).

Use a large font size (ie Arial H1) for your main header text, smaller font sizes (Arial H2, H3) for your subheadings and a point or pixel size of 10 or 12 for your body text.

Generally I use Verdana 10pt for body text and Arial text for headings.

5. Utilize Cascading Style Sheets (CSS) - these enable you to easily create a consistent font style across your entire web site. If you want to change the font on all your web pages, you just need to change one style sheet.

CSS allows you to easily use comma-separated list of fonts (ie Verdana, Arial, Helvetica, sans-serif). The browser will use the first one it comes to in the list that is installed. If none of the type faces in the list are available, it reverts to the default.

Writing correct web copy using fonts that are easy to read and readily available, not only adds character to your web pages, but shows you care about the experience of your visitors.

Resources

Web font readability study.
http://www.wilsonweb.com/wmt6/html-email-fonts.htm

Hundreds of free fonts
http://www.fontfile.com