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When computers were all text screens (unable to display images except of special high end workstations) the only erotica around was in written form. Much of the original computer erotic stories came from magazines like Penthouse, Playboy, and Hustler, who all ran erotic stories sections in their magazines. Text travelled well from computer to computer, through the BBSes and file traders of the day, and thus, this was the original online porn.
With the move to higher and higher connection speeds and the ability to send and display images, you would think that erotic stories would fade away. That however has proven not to be the case, and new erotic stories are written on a daily basis. Many people find this type of erotica to be a little more thrilling, requiring an actual imagination and allows the authors to express their inner dreams and desires, even if they are not possible.
* Go Stories - Links to some good erotic stories sites * Taboo Stories - One of the net's most complete erotic stories sites * Free Erotic Stories - a blog with plenty of free erotic stories * All Free Erotic Stories - Sex stories blog updating regularly * Gangbang Stories - All stories about threesomes, foursomes, and girls pulling the train!