Could someone educate me about the dignified transfer ceremony?

I have been unspeakably moved watching the pictures of our President participating in the dignified transfer ceremony at Dover the other day. But I know so little about the actual ceremony.

Could someone familiar with this explain what it's all about?

Among other things, I'm curious about the fact that, apparently, the President participated in several separate ceremonies, one for each of the fallen soldiers who arrived that morning. There are photos of him walking up the ramp of the C-17 each time. Does the party escort each casket from the plane? Is this ceremony conducted by all of the branches of the military?

I'm sorry to have so many questions, but I am very interested in learning more about this and, I assume, other DUers may be, as well.

Thanks in advance.

per....

Minutes before Obama’s arrival, an Air Force C-17 transport aircraft landed in the base, carrying the bodies of eight Army soldiers killed by a roadside bomb and seven soldiers and three DEA agents killed in a helicopter crash.

A military chaplain accompanied Obama and other officials onboard and said a prayer over each casket before it was transferred out of the aircraft, military officials said.

http://belowthebeltway.com/2009/10/29/obama-at-dover-as-caskets-return-home/

One of the reasons he looked so "good" doing it (although I hate to describe it that way given the circumstances) was that, by the time he did that last salute for Sgt. Griffin, he had already done it 17 times.

And knowing that Barack Obama doesn't half step on ANYTHING, it would not surprise me to know that, at some point in the last year, he enlisted a bit of "how to salute properly" coaching by some of the military officials who now surround him.

He wrote in one of his books how he always admired the Army (?) base near his home in HI. The organization, the crisp cleanlieness, the pomp and circumstance of it all.

Scroll down.

Dignified Transfer Policy

I don't much agree with the author's opinion, but he gives a good description of the transfer policy, who is present for each soldier, etc.