HN was created in 2007 by Paul Graham originally as a "news aggregator" with a comment facility, as part of his YCombinator venture capital startup incubator thing. I think the idea was to source links to news of interest to the tech/startup world.

Somehow it still thrives under his benevolent though remote stewardship (he rarely post himself, realising you can't be a "player character" in the forum that you are in charge of). I think mainly it works because it has remained consistently usable and well moderated and nobody has messed around with it.