An AE is generally a person. It is supposed to represent a part of their CBers personality. For example, Georgia is my energetic, optimistic, extroverted side -

Hello! That's me!

Diana is my calm, sweet, helpful side.

Hi there. 

And Arrow is my sarcastic, easily annoyed, anti-social side.

I'm not anti social. I just avoid social interaction.

That's literally the definition of anti social...

Anyway, a CAPTCHA is the code that you put in to post a comment on the CB. Some CBers give their CAPTCHAs names and make them into characters, often animals. They speak in five-letter increments, because captchas are five-letter codes. For example, my captcha is a puppy named Memphis. 

~hello~ ~iiiii~ ~ammmm~ ~memmm~ ~phiss~ ~theee~ ~puppy~

Translation: hello i am memphis the puppy.

Hopefully this helped, AEs and CAPTCHAs are very complex ideas, I guess.  

AEs are generally beings that talk naturally. They represent sides of a CBer, as MM said. 

I'm Timeshifter, Night's most responsible AE. 

I'm only going to allow Time and Ilian to represent, as the rest will go crazy. 

&Iiamm& &Ilian& &Nigts& &mstqu& &tcptc& &hahlo&

((Translation : I am Ilian, Night's most quiet CAPTCHA. Hello.))

CAPTCHAs are the 5 letter spam box at the bottom of your post, you have to fill that in. Some CBers have multiple, some have one, others have none. 

~Nightfall 

Awesome! Thanks Guys! Imma make so many of them.

You all ready have three

SO. MANY.