I had never seen Transformers before, only as comics, but my local tv-station just started sending two different Transformers series, I didn't get the first episodes, so I've got a couple of questions:

What's the difference between the two kinds of Transformers?
What is Cyber Key Strength (I think it's called)?
How did Earth get involved?

Hmm...you'd probably be better off checking the official website/nostalgia sites...

First off, what you need to understand is...what they are showing you on TV today is NOT Transformers.
And if you are getting new episodes of He-Man, Teenage Mutant Ninja Turtles, or GI Joe....those are not REALLY them either.
They are toy companies pathetic attempt to market what was great from the 80's and market it to a new generation so they can fleece their wallets as well.

Transformers, if you REALLY are interested...has a great storyline history with great characters.
I agree with Trimac20, you should fine a nostalgia site, and go from there.
Also, you can pick up the Original Transformers comics from Marvel in a comic book store pretty cheap.
And..as if that werent enough.... all 3 seasons (and the movie) of the original Transformers are all available on DVD.

Because I'm sure you would want to learn more about the ORIGINAL Optimus Prime and Megatron...instead of
Optimus Prime the IV and Megatron the VIII. or whatever they are calling themselves these days.

I agree, find a good nostalgia site.  The story had to do with two races of transforming robots (Autobots and Decepticons) from the planet Cybertron that were at war with each for thousands of centuries.  They travel the galaxy looking for new sources of energy, the good guy ship is hijacked by the bad guys and they crash land on a primitive planet called Earth where all of them are seemingly dead.  4 million years later a volcanic eruption reactivates the main computer and the robots are reassembled, with no quick way to get back home to Cybertron.  So both races are stranded on Earth.  Thus was the 80s TV series.  The animation was done in Japan, but the mythology was clearly fleshed out by Americans, i.e. Marvel Comics.  If you watch it now it may seem a bit goofy, but back then the storylines were considered much, much more mature and intelligent then anything that Hanna-Barbarra (i.e. something like Scooby-Doo, Superfriends) was putting out.  

A 90s TV series existed that took place during the pre-historic time that the ship was crashed on Earth, with another set of Transformers.  I am not well versed in the Beast Wars TV series though, I hear it is better then it is given credit for.

You're about 34 correct?  I think you were about 2-3 years too old/too cool to have cared about Transformers when they hit the scene in 1984.  Well most fans were in grade school at that time.  That can be all the difference in the world between being 10 and 13 or 14.  Anyone can be a fan, hell I obviously still love the old series that I grew up on.  But it tended to target children, for instance I was 9 at the time.

Thanks chris for that explination!! I was just about to inform him of the Autobots and dececepctacons (excusemyspelling) But this NEW crap IS NOT THE TRANSFORMERS!! AUTOMUS PRIME IS AN 18 WHEELER!!! NOT AN APE!!!  Remember Megatrons screeching voice? Remember the sound they made when they transfomed? Remember that one transformer that transformed into like ten different things? Remenber the dino-bots" ("Grimlock Break") Remember the construct-a-cons? I am a real 80's kid!!!!

My fav characters were Megatron..because he was ruthless...and Soundwave..cuz he had that cool voice and had all those tapes (Laserbeak,Buzzsaw,Ravage,Frenzy,Rumble,Ratbat).  I used to love Shockwave in the comics..they didnt use him too much in the cartoon.
The constant control for leadership between Starscream and Megatron was great too.

I remember forcing my mom to drive me to a toy store out of town because it was the only place I could get Soundwave.

I still have all my original toys too...they are not in the best of shape...cuz back then we played with our toys....but at least I have them.