There were eighteen skills in 2006. Gone are Construction, Hunting, Summoning and Dungeoneering. Constitution was still called Hitpoints.
In order to create anything in your inventory, each item had to be clicked, every single one. Unformed bow on bowstring; herb into vial.
And, incidentally, those herbs would have to be identified first, because nobody knew what they might be. This was an age of peering at the colors, trying to guess from the exact shade of green.
The Wilderness was there, of course, before the time when it was removed in a bid to combat Real World Trading and bots. (A noble pursuit sullied by 2012, when many players accused Jagex of simply buying into the very same industry.) PKing clans ruled supreme.
Questers (myself included) could embark upon eighteen f2p and eighty-six P2p quests. The big names amongst them were the Underground Pass, Mourning's End Parts 1 and 2 and Monkey Madness. For those adventuring around Varrock, Romeo and Juliet still wandered around.
There were twenty mini-games, including the classics Castle Wars and Pest Control. The random events could be dangerous to those away from their keyboards or cheating via bots; and treasure trails were worth doing.
But more to the point, everyone had a level playing field, regardless of real life status. You rose or fell on your merits only within the game.
For more memories, there is the RS2006 Wiki to peruse.