Word processing and graphics program come with a selection of fonts that give you some flexibility for displaying text.  The default fonts that can be used with programs such as Microsoft Word or Adobe Photoshop are determined by your operating system.  Windows XP, for example, includes a few dozen fonts ranging from blocky athletic fonts to scripty craft fonts to symbol fonts.  Many other fonts are available besides the most common ones that are packaged as part of an operating system.  Typically these fonts have .ttf, .otf, or .fon extensions.  To see what’s available, you can do a web search for “free fonts” , “download font”, or something similar.  When searching for fonts, you’ll find that, besides the free ones available, there are many available for purchase as well.

Once you’ve found the font you want to add to your operating system’s font collection, download it onto your computer.  Normally the file you download will be a compressed .zip file.  Often a particular font will have a few variations, so inside of the packaged .zip file there will be a few font files.

After you’ve downloaded the .zip file containing your new font(s), the method you use to install it depends upon the operating system you are using.  For Windows XP and previous versions of the Windows operating system, you need to copy the font files you downloaded into your Windows font directory.  That directory is located at C:\Windows\Fonts (or at C:\WINNT\Fonts for Windows 2000 or Windows NT).  If you are using Windows Vista, you can right-click on each of the font files and select “Install”.   After you have installed your font, you can open your word processor or graphics program and place some text on the page.  In the font selection menu, you should see the new font you just installed.  If you don’t recognize your new font file in the list, you may have to make sure you’re looking for the right name for the font.  Sometimes the names used for a font that shows up in the font selection menu are slightly different from the name of the file you used when you were installing the font on your computer.

Example
I needed to install a font called Sports Night onto my computer so that I could make some changes to a logo that was sent to me using that font.  That particular font is available for free, and I was able to download it as shown below:

After I saved the font on my computer, I right-clicked the .zip file (SportsNight.zip in this case), and I extracted the font files onto my computer’s Desktop.  [In order to work with .zip files, you will need a software utility that allows you to do so.  Most new operating systems come with one built in.  If yours doesn’t, you can easily find a free one online.]  Then I selected the eight files that comprise the different versions of the SF Sports Night font.  I copied those files and pasted them into my C:\Windows\Fonts folder, as shown below.

Now I can open up Photoshop and use the new fonts.