how do you add fonts in PS

the tital says it all

you dont actually add fonts to PS...you add them to your computer...easiest way it to download the fonts, go into your control panel and choose the fonts section and it will open your windows fonts folder, then click and drag the fonts over and it will show them installing on your system, then your done...MOVED

Yes, you should restart Photoshop when you do it.

Warning: the more fonts you add, the slower you computer will be.
Adding like 20-30 isn't going to make a difference, but when you add 2000+ you will notice a significant difference in starting up, and when programs load fonts.