Capital letters are important and therefore one should say it is essential to know how to use them in the correct way.
Capital letters are the difference between helping your Uncle Jack off a horse and helping your uncle jack off a horse. (sorry for being rude, but isn’t it a good example?;-)
Want to know more about Capital letters? Watch this fast paced video about when and how to use then and remember that the overuse of capital letters ,when writing ,is considered by most people rude.