What are Panels for?

[Sadistic Rainbows]

Heard about them.
What exactly are they? o:  

[Glacirus]

Panels consist of various things. Executives from producers to talk about part of the industry, voiceactors talking about their jobs, mangaka talking about their works, announcements of new dubbing/future dubbing/bringing to your area. They're there so you can keep your finger on the pulse of the anime/manga world and what new thing is coming your way. Also a great way to get close to your favorite VA/artist at times.  

[ll dell Orso ll]

Not only are panels like Glacirus said...
But they are also informative about culture.

There are many Lolita Panels and Cosplay Panels that show you the how-to's and such of fashion and costuming.

Our local con is even planning on having a Shogi and a Go Panel to teach con-goers how to play.

A con in our state is actually starting Activity Panels.
These panels require a small fee to attend but you come out with something cool in hand.

For example: I'm excited about the sushi panel.
You pay a few bucks and they show you how to make your own sushi. I already know how to roll and handle sushi but you can't pass up the chance to make your own sushi with others! >w<

They are also having a wig styling panel where you pay a small fee and get a training wig ((cheap wig)) to learn first hand how to style a wig.  

[RyanJakobi]

Panels are sometimes the best part of the cons for the folks who are just too old for the cosplay aspect. They talk about boring and/or interesting things, and there's lots of active participation. I know in Otakon there are several professors who come in and help explain anime culture to parents, so that's always useful.  

[Sadistic Rainbows]

How would cosplayers get their own panels?
[i.e. Parle Productions]  

[ll dell Orso ll]

Sadistic Rainbows

How would cosplayers get their own panels?
[i.e. Parle Productions]

You could contact the staff in charge of the Panels at the convention before the convention starts... a few months before the convention starts. If you are selling things then just get an Artist Alley table. If you want to do demonstrations, run games, or present information then you can ask if there is a spot open in the Panels.
Of course you would also need to fill out the proper paperwork.

Thats all I've been told to do for the local conventions. I usually only join in on game panels and offer panel ideas. Never was one to run one myself though...  

[TigerLilyChick]

Sadistic Rainbows

How would cosplayers get their own panels?
[i.e. Parle Productions]

Adding onto what Charmful IncarnatE said, signing up to do a panel isn't always guaranteed. I know that Otakon does this, but I do not know what other anime conventions do.

For Otakon, you apply to do a panel. The staff reviews all panel applications and the staff chooses which panels will make an appearance at the anime convention that year.