We'd be in the third decade to my knowledge.
I started online about 1996 and what one could call an online community was already established. H2O is the best remembered part of it. So, if we said 'from before 1996 to now', that'd be just over twenty years, thus we're at least in the third decade (or just entering the third).
*sighs patiently*
I suggest you read up on the history of PDF, and then ponder how many 'decades' CofC was around in PDF form, easily available (with the cost of software, printer, and a PC!) for downloading and printing before 2000. That would be the only reason to pirate it instead of buying it, right? After all, it was not an expensive book, correct?
Computers and administration was my field from 1980 - 1992, so I can accurately say that until the mid 90s, Windows was not even the standard in all offices. Working at the telephone company in 1992, we were still using DOS as our OS (I worked with the Information Centre, producing documents and even a textbook, yes, little old me, was a techie in my previous life, so you picked the wrong person to try and make this point with). So, the "decades" argument you make is, well, let's just say it makes no sense to this poster.
http://www.prepressure.com/pdf/basics/history/2
* know your facts before you make a sweeping statement class