View <a href="http://khanacademy.org">Khan Academy</a>'s library of over 4,000 educational

videos. Topics covered include: general science, biology, chemistry, physics,

math, finance, history, the humanities, and more.

Khan Academy's library of videos is available free of charge. Teachers,

students, scientists - people form all walks of life - will find Khan Academy's

materials immensely valuable and engaging.

You can take individual videos, or entire topics offline to watch when you don't

have a network connection. Follow along, skip ahead, or go back by navigating

subtitles, and connect with your Khan Academy user account to track your work

and earn achievements.

Creator