No matter what kind of computer you're using, installing fonts for normal desktop use goes like this:
Below are some Step 2 instructions specific to certain operating systems.
If it's just a single font, double-click it and hit 'Install Font.' If there are multiple fonts, follow the above procedure for each, or better yet, open Font Book, then select and drag them all at once to Font Book's center column. Find Font Book by opening a Finder window, selecting 'Applications,' and scrolling down to 'Font Book.'.
If it's just a single font, double-click it and hit 'Install.' For multiple fonts, hit the Start button, then Control Panel, Appearance and Personalization, and then choose Fonts. Drag and drop the new fonts here.
If it's just a single font, right-click on the font file and then select 'Install.' For multiple fonts, follow the directions above for Windows 7 / Windows 8.
Drag and drop the font files you'd like to install into the 'Fonts' folder. This is generally located at C:\Windows\Fonts.