Back in 1996/1997 or so, I realized that I could manipulate infoseek's search engine by putting the keyword on the page a couple of dozen times. My business site took off and made good money! I'm sure I wasn't the first person to do it, but other individuals like me, realizing how easy it was (at the time) to manipulate the results got the 'industry' started I think. Just a bunch of individual internet guerilla marketers trying to figure out how to find business success online got it started. Those were fun times! I had hundreds of top ten results and lots of easy business! People would email me to say... 'gosh, I was looking something up and just happened to find you' - heh, heh, heh How 'bout that. I don't know if that is really an 'invention', just a bunch of scrappy individuals taking advantage of an opportunity they discovered.
I invented Black Hat back in 1996. I made a lot of spammy keyword stuffed dore way pages. Altavista loved them.
Yep, good memories - it was so easy back then And no forums or having to ask questions to figure out what was going on. No banning of websites. You just tried something and a week later it either worked or it didn't and you try something else.
I think time has created it because search engines have to operate in constraint of displaying few (10 mostly) serp for particular search and number of pages for that search is continuously growing in number.