When do you use email

I use emails mainly to contact my friends in other countrys, or send and recieve work from college. The major benefits of using emails are that you can send files and pictures along with them, also it quicker then sending a letter also it is granteed to get there where as letters and other mail may get lost in the post. Also it saves companies alot of paper and time, for example if they have the same letter going out to a big group of people then with an email all you have to do is add all the recipitants to the mailing list, unlike with a letter where you have to write out the adresses separtely.