Your Internet Consultant - The FAQs of Life Online
Even the most verbose of writers' messages easily fit under the limitations of the most restrictive networks. E-mail messages are usually one to three kilobytes long. In comparison, this chapter (just the text, sans formatting) is about 75 kilobytes long. (If you're reading this, you'll know that it successfully made the trip from the Internet to my editor's CompuServe account.)
I have sent e-mail messages that included large binhexed programs that were 3 or 4 megabytes in length. I sent these messages between sites in the continental United States over connections that I knew could handle the obtuse files.
You shouldn't send huge e-mail messages over transcontinental links. Many of these Internet connections are excruciatingly expensive, and the folks who use them often pay for each byte that passes their way. Similarly, networks such as FidoNet are passed between computer systems by long-distance phone calls. Their owners pay the bills out of the goodness of their hearts, but they become annoyed when forced to pay for wasteful use of the network bandwidth. Gratuitous use of electronic mail in both these situations annoys people and is likely to get you yelled at.