ARPANET - In October of 1969, a connection was made between computers at UCLA and Stanford University. Called ARPANET (Advanced Research Projects Agency Network), the networked computers were the first in history to ever utilize packet switching, making them the great grand daddy of the Internet as we know it today. The research that led to the completion of the project was funded by the United States Department of Defense.

Email - If you ever run into Ray Tomlinson, take a moment to thank him for helping to shape the modern world. In 1971, Tomlinson created the world’s first inter-host email system on ARPANET. In order to indicate what machine email users were sending their mail from, Tomlinson decided that an ampersat would be used, creating the user@username.com format that we’re still rocking today.

The Transatlantic Internet - Back in 1973, as the U.S. Senate plunged into the Watergate hearings, researchers were busy pimping ARPANET out with it’s first trans-Atlantic connection to the University College of London in the United Kingdom. By that point, upwards of 75% of all ARPANET traffic consisted of email: A fascinating statistic, given that the first email client wouldn’t be developed for another two years.

The Birth of TCP/IP - In December of 1974, Network Working Group members Vinton Cerf, Yogen Dalal and Carl Sunshine published a paper that started ARPANET down a road that would shape the internet as we know it today. The paper was called ‘Specifications of Internet Transmission Control Program’, and it detailed a method for interlinking independent networks through the use of a transmission control protocol. This concept matured into TCP/IP: Transmission Control Protocol/Internet Protocol.

The Original Email Client - With interconnectivity between multiple networks rapidly becoming a reality, the number of email users swelled to unprecedented numbers. This massive influx of new users was likely due in part to the fact that in 1975, a University of Southern California John Vittal developed the first email client. Called MSG, the program offered amazing new features such as buttons to reply to or forward mail with relative simplicity—functions we all take for granted today.

The Modem - As computers became compact and affordable enough for many hobbyists to keep in their homes, a demand for single user network connectivity emerged. In response to the yearning of the growing computer geek community to dial-in, Dale Heatherington (pictured above) and Dennis Hayes created and marketed the first PC modem in 1977.

SPAM - With the advent of interconnected computer networks, email and the growing number of users leveraging computer technology in their daily lives, it was only a matter of time before someone decided to ruin it all by firing off an unsolicited email to unsuspecting recipients. In 1978, Gary Thurek and his assistant sent word to close to 400 ARPANET users about a new computer product. The event marked the birth of spam. Thanks Gary. Thanks so much.

Usenet - As anyone will tell you, email’s great, but even with the advent of Send/Reply all, it’s still far from inclusive. Realizing this, Jim Ellis and Tom Truscott created a method for network connected computer users from around the world to blather on about the same topic by posting their thoughts on public message boards sorted by category. The system was called Usenet, and it went online in 1980.

DNS - In 1983, in an effort to make the Internet more user-friendly, Paul Mockapetris drafted the first implementation of the Domain Name System (DNS). Before DNS, Internet users were forced to enter the numerical IP address of any web host they wanted to visit. This was, we’re sure you’ll agree, a drag. Implementing DNS made easier network and Internet navigation for users and few headaches for the network administrators responsible for keeping HOST.TXT files up to date.

IRC - While email and Usenet were hot back in the day, Internet Rely Chat (IRC) was the new hotness by the time that 1988 rolled around. Allowing for real-time text messaging from any network-connected system. Up until the advent of IRC, realtime computer-based group chat, data/file sharing and private messaging were the stuff of science fiction.

The Virus is Born - 1988 didn’t just mark the introduction of IRC. That same year, the first recorded internet-based attack was unleashed by Robert Tappan Morris. Dubbed The Morris Worm, the malicious piece of code caused significant service interruptions across a large swath of the Internet. Morris’ efforts also resulted in another first: The first U.S. conviction of an individual under the 1986 Computer Fraud and Abuse Act. Oops.

America Online - For anyone that’s ever used an Compact Disc as a coaster during college or heard the phrase ‘you’ve got mail’ seep out of their computer’s speakers, 1989 was a very good year as it marked the launch of America Online. The sloppy seconds of Apple Computer’s Applelink program, AOL was the first multi-platform Internet service designed for widespread use by consumers.

The Web Goes World-Wide - 1989 was also the year that the term ‘World Wide Web’ was coined, as part of a proposal to CERN suggesting an efficient method for tracking information on “…complex evolving systems and derives a solution based on a distributed hypertext system”. Written by Tim Berners-Lee, the WWW Proposal detailed a method for using a hypertext system to organize and share information via the Internet. The protocols were adopted, and implemented in 1990.

Webpages - What would the World Wide Web be without a few webpages? In 1991, the first webpage in the history of the internet went live. While it wasn’t much to look at, the page explained what the World Wide Web was, what it was good for and what sorts of information could be found by navigating it.

Search - In the same year that the first webpage made it online, the Internet also enjoyed another significant breakthrough: the introduction of the first content-based search protocol. Gopher was a TCP/IP layer protocol created to search for, distribute and retrieve documents on the Internet. While Gopher was fast and efficient to use when shoveling data, the protocol failed to catch on with Internet users, who largely favored surfing the World Wide Web.

The Browser - Designed by the National Center for Supercomputing Applications, Mosaic was released in 1993. While there had been other web browsers prior to the Mosaic’s launch, it was the first application to make the accessing the Internet unintimidating and easy. Mosaic’s user-friend nature made for a massive surge in the use of the World Wide Web. Modern browsers such as Camino, Internet Explorer, Firefox and Chrome still retain may of the features first offered by Mosaic.

Webmail - While electronic mail had been a fixture in the computing world since the mid-1970s, the introduction of web-based email services didn’t occur until close to two decades later. Hotmail was launched in 1996, and made it possible for the first time for anyone to access their email from anywhere in the world so long as they could wrangle an Internet connection. The insanely popular service was sold to Microsoft the following year for a cool $400 million.

Google - In the 43-year history of the Internet, Google is a relative newcomer, but man, what an impact it’s made. At the time Google hit the net, search engines were returning results to users based solely on how many times a search term appeared on a given webpage. Google’s creators Sergey Brin and Larry Page further refined this by designing a system that would also analyze the relevance of a page and the relationship between websites. The rest is history.

Napster - Although computer users had been sharing files via IRC and USENET for years, P2P sharing didn’t really come into its own until Napster hit the Interwebz in 1999. Boasting a user-friendly interface and massive number of illegally shared user-uploaded MP3 files, Napster was a massive hit with music lovers around the world. That said, the music industry hated it, and saw to it that the first iteration of the service was shuttered in 2001.

SOPA - 43 years after its inception, the Internet is at a turning point, thanks to a bill currently being tossed about the U.S. Senate called S.O.P.A., the Stop Online Piracy Act. If passed, the bill would allow the U.S. Department of Justice to seek court orders against websites accused of copyright infringement anywhere in the world. While SOPA has lost considerable support recently, those against the bill fear that if it were to pass it would severely hamper free speech online.