The Internet began as a Cold War project to create a communications network that was immune to a nuclear attack. In the 1969, the U.S. government created ARPANET, connecting four western universities and allowing researchers to use the mainframes of any of the networked institutions. New connections were soon added to the network, bringing the number of "nodes" up to 23 in 1971, 111 in 1977, and up to almost 4 million in 1994. As the size of the network grew so did its capabilities: In its first 25 years, the Internet added features such as file transfer, email, Usenet news, and eventually HTML. Now, new developments come to the Net one right after the other. It is this explosive growth in recent years that has captured the imagination of computer users the world over.