Basically what happened was... the manga for FMA was being written, and the anime was started shortly after. The anime only followed the manga's storyline briefly (probably about a couple of chapters worth), and then it diverted to the anime director's interpretation of how the story would turn out. FMA Brotherhood was then later developed a couple of years later, and it followed the manga's storyline. FMA Brotherhood is still ongoing, while the first FMA was finished a while ago now, with a movie tying up loose ends. It's quite interesting that although the first anime's adaptation had a completely different storyline and explanation for why certain things happened... it still made a lot of sense, despite being so different to how it is to the manga's intention.
On to the plot... FMA is set in a world that would be of similar time to World War 1 and 2. Also, there is a common practice known as alchemy, which involves the transmutation of one thing into another. The fundamental law of alchemy was that you can not create anything out of nothing, and thus why human transmutation is forbidden. The main characters, Edward and Alphonse Elric did not know about this when they were little, and they attempted to perform human transmutation on their mother who had recently died. Since you can not create live through alchemy, the transmutation failed and it resulted in Edward losing an arm and a leg, while Alphonse lost his whole body. Some quick thinking allowed Edward to use alchemy to attach Alphonse's soul to a suit of armour. Thus the general storyline is based on these 2 brothers trying to find a way to restore their bodies, and this is consistent in both versions of FMA. It's just the later parts which differ a lot.
Aside from the differences in storyline, the main thing I noticed was that the first FMA is of a much darker and more serious atmosphere, whilst FMA Brotherhood is more cartoonish and puts more emphasis on the comedy aspect of it (i.e Edward's personal hate of people calling him short). I'm not really sure which one I favour more, but theres definitely a clear difference in the way the animes are shown.
There are a heap of characters throughout the anime, but I'll just discuss a few of the main staples:
Edward Elric - Obviously the main character. He has an 'auto-mail' arm and leg, to replace the limbs that were taken during the failed human transmutation. It's essentially a fake limb made of metal, but it connects to the person's nervous system allowing him/her to control it as it if was an actual limb. A lot of people make comments about him being short, which he really hates, especially when they think Alphonse is the older brother due to his armour being much larger than Edward. He becomes a state alchemist in order to obtain more information about how to get their bodies back.
Alphonse Elric - The younger brother of Edward. He is superior to Edward in hand to hand fighting, although not as gifted in alchemy. While Edward is the hot-head, Alphonse is the calmer, thinking type. Both Alphonse and Edward are really soft hearted, but Alphonse shows it more... while Edward is more of the 'put on a hard face' type of person.
Winry Rockbell - The childhood friend of Edward and Alphonse. She is an auto-mail mechanic, and she maintains Edward's auto-mail. She is very enthusiastic about her work, and she gets extremely excited about anything related to auto-mail. Apart from that, she's a very typical kind of girl that you expect the lead female to be.
Rating - 9/10. I almost gave it 9.5, but it's not quite up to the standards of some of the other animes I've seen, although it has a great storyline. If you are going to watch FMA, I'd recommend watching the earlier version first, before you watch FMA Brotherhood. Main reason is that FMA Brotherhood is still on-going, but I think it's better to watch the more serious one first, before watching the one that focuses more on comedy. Also, it means you can see how the anime director interprets it, as opposed to how the manga writers intended it to be. However, if you're not a fan of dark kind of anime with a lot of gore, then maybe just watch FMA Brotherhood. I do admit that there are some pretty upsetting scenes in the first FMA, and some that made me cringe.
Below is a picture of 2 main characters; Edward Elric (left) and Winry Rockbell (right).
