When email became available, it was very popular, but people soon found that it had some shortcomings. Often, a group of people with similar interests wanted to simplify the process of communicating via email. At first, if you had five people around the world who were interested in your research topic, you would simply send the email five times, once to each colleague. This quickly became unwieldy if you shared an interest with a larger group. The solution was to use the distribution list feature built into many email programs. You could learn the email addresses of all the people with similar interests, and store them as one name in your address book. This worked fine as long as the list of people stayed relatively short, and the people on the list didn't change too frequently. This kind of approach had some setbacks, though. If a person no longer wanted on the list, every other member of the list had to remove that person from their own personal copy of the list.List management became a messy job, so computer scientists developed a program that could automate the mailing lists.