Sega NetLink (also called Sega Saturn NetLink) was an attachment for the Sega Saturn game console to provide Saturn users with internet access and access to email through their console. The unit was released on October 31, 1996. The Sega NetLink consisted of a 28.8 kbit/s modem that fit into the Sega Saturn cartridge port and came packed with a browser developed by Planetweb, Inc. The unit sold for US$199, or US$400 bundled with a Sega Saturn.
The NetLink connected to the internet through standard dial-up services. Unlike other online gaming services in the US, one does not connect to a central service, but instead tells the dial-up modem connected to the Saturn's cartridge slot to call to the person with whom one wishes to play. Since it requires no servers to operate, the service, in theory, can operate as long as at least two users have the necessary hardware and software, as well as a phone line. 
In Japan, however, gamers did connect through a centralized service known as SegaNet, which would later be taken offline and converted for Dreamcast usage.
While the NetLink was not the first accessory which allowed console gamers in North America to play video games online, it was the first to allow players to use their own Internet Service Provider (ISP) to connect. While Sega recommended that players use Concentric, the Sega NetLink enabled players to choose any ISP that was within its technical specifications. The device was capable of connecting at a 28.8 kilobit/s connection in America and 14.4 kbit/s in Japan. The success of the Net Link was limited by factors such as high cost, the small number of Saturn owners compared to the competition, and lack of games that took advantage of Net Link capabilities.
In Japan, the NetLink required the use of smartcards with prepaid credits. These smartcards or "Saturn media cards" cost ¥2,000 and one game credit was ¥20, which means that one could play about 100 games per card. The Saturn had a floppy drive and printer cable converter (both Japan only) which could be used with the NetLink. A web browser from Planetweb was included, and a mouse and keyboard adapter were available to simplify navigation.
Before the NetLink was not made available for wide release in Europe, Sega performed a test release in Finland before deciding not to widely release the unit in the European market.
Despite the Saturn's relative lack of success in America, the NetLink had a number of users, and five games were released domestically that supported it. Sega of America originally wanted to sell 100,000 NetLinks.  Sales records show that the Sega sold 40,000 units. 
In theory, NetLink games can still be played today, as the NetLink modem can use direct-call to connect two players to each other, but the "NetLink Zone" method, which allowed gamers to meet in IRC, can no longer be used as the servers were shut down in 2001.
The NetLink Zone connected to an Internet Relay Chat server irc.sega.com which was changed to the server irc0.dreamcast.com on the release of Sega's Dreamcast. These servers were originally run by Sega employees but were given over to be run by NetLink chat users Leo Daniels and Mark Leatherman.
Games compatible with NetLink
- Vinciguerra, Robert. "Discovering the World Through a Sega Saturn NetLink". The Rev. Rob Times. Retrieved 16 December 2013.
- News article from cnet written before release http://news.cnet.com/Sega-catapults-to-the-Net/2100-1023_3-239291.html.
- Soohoo, Ken. "Rare Sega Saturn File 4.035 Golden Net Link Web Browser Resurfaces; Plus Republished 1998 Interview With Then Planetweb CTO Ken Soohoo". The Rev. Rob Times. Retrieved 16 December 2013.
- Learn Planetweb's Self-Download Feature
- Sega Saturn NetLink League: Information about the NetLink and a resource to find other NetLink players
- Netlink & Dreamcast Old Users @ Way2Live4U.com