the reason is so people will stop confusing RPGs that carry the name "dungeons & dragons" in their name.
all D&D games are not alike. they are in fact each different games with different rule.
calling a game only D&D just defines that it is a "sword & sorcery" fantasy role-playing game produced by TSR [Tactical Studies Rules] or the companies new owners/copyright holders.
now for the editions.
Dungeons and Dragons










d20: AKA 3e, 3.5e. all those on the market today.


now a lot of those are similar but play differently. and of course the d20 system for Dungeons and Dragons 3rd edition (or 3.5) is very much different. so when describing D&D i hope poeple will use the right term so people will know what they are talking about and not be confused into thinking that d20 is the ONLY system, cause the older version that started the "pen-and-paper" role-playing games are still being played. wink
which brings us to another system.
Advanced Dungeons & Dragons
1e: this is the book written by Gary Gygax which compiled all the rules into a new edition of the game with more rules to cover various things.




2e: written after Gary Gygax was removed from TSR and taking his new game to yet another level. not saying better, cause some still use 1e. just another direction with similar aspect of the more advanced rules.

2.5e: this added onto the 2e version with the "player's options" rules. also completely reworked the psionics of the game.

Hackmaster: while not made by TSR it is 1e with a humorous side. the rights to produce this game was obtained through a lawsuit brought about when TSR and/or WotC (Wizards of the Coast, the new owners of TSR products which is now owned by Hasbro) made an anthology of their periodical called Dragon Magazine into "the Dragom Magazine Archive". Kenzer & Company had been creating the comic "Knights of the Dinner Table" which appeared in that magazine. and when the CD-ROM archive was produced it violated contracts which allowed only a certain number of copies of the articles to be published. Kenzer & Company was not the only artist or writer who was violated, but they are the only ones that got substantial compensation for their works. and allthough it is not an official Dungeons & Dragon product, but it does use the rules of 1e written by Gary Gygax and has the license to them.


again AD&D in its various versions are so different that they are not playable with each other without converting between the systems.
D&D and AD&D likewise are different.
Advanced does not mean it is for more experienced players, but a completely different game. so whether playing basic or advanced means nothing for knowing how to play the other. only some similarites and the ability to role play is the same in both. if you were to want to start playing D&D you should play the edition you are wanting to play. you can not move from one to another as the terms Basic and advanced seems to sound.
basic does not mean beginner, only and older version with more basic rules. when elf and dwarf were a class each. that in itself should show how much they can be different. wink
well i hope someone has learned something from this. feel free to discuss different editions of the game, but keep it civil. i have a preference of which edition i like, and i am sure everyone else does.
but just remember 3e/d20 is not the only game. so when you say D&D/DnD/etc. keep in mind you are talking about an entire genra of role playing games made by a particular company. and dont be surprised when either on forums, or in stores, you hear things that you have never heard before since those people may be discussing one of the root systems of the game.
happy adventuring!