Is it wrong to use a alias online?

It's not wrong to use an alias online as long as you're not using it questionably.

Nope.

What are alias? (Dont kill me plz)

Nope, I use a name I made up Katherine Genevieve Hunter, but I dont use it for facebook and social media networks like that... it is alot safer

Omg I love sword art online

Many things I cant explain

We'll in America it is illegal to take on an alternate alias online, though people always do it anyway, nobody has ever been arrested for it, so is it wrong? Legally yes, but the true question you should be asking is, does anybody care if it's wrong?

That is up to you, it is most likely safer to use an alias online...but it is truely up to you whether you use one or not.