ETA: Over at the little_details post, someone linked me this site which is chock full of detaily goodness. She has done the medals for Jack, Sam, Hammond and Jacob. You can see them here. Her Jack and Sam stuff agrees with mine in terms of the ribbons, but not the devices (clusters/stars), in some cases. Which is fine, because I had trouble figuring them out anyway. :-D
Insignia Badges: These are the silver pins worn above the stripes, which indicate the role, occupation, skill set or division of the Air Force the person works in. A plain one indicates a normal rank, one with a star on the top indicates a senior rank and one with a star on the top with a laurel around it indicates a master rank.
Stripes/Ribbons/Medals: Each medal awarded has two parts - the ribbon and the metal medallion. Rather than wear the heavy medallions of all your medals, you wear a stripe replica of the ribbon part. Stripes are worn three across rows, in the order of precedence (basically how big an honour it is to receive them), from top to bottom, left to right. So your most awesome stripe is in the top row, to the left and then it goes down from there.
Oak Leaves: When you are given an award more than once, rather than add another identical stripe, you are given a bronze oak leaf cluster pin to put on the stripe to show you've gotten the same medal again. Each time you are awarded the medal, you get another oak leaf. So, if a person has 3 oak leaves on their stripes, they have been given that medal four times. If a person receives the medal more than five times (a stripe+ four clusters), a silver cluster is given and replaces the four bronze ones. This continues for each subsequent awarding of five bronze oak leaves.
More Info: Here is an excellent resource to find out what the individual ribbons mean.
(click on the images for them to get bigger)
* = indicates one oak leaf cluster
Gen. Jack O'Neil (circa S10 'Avalon')
|USAF Master Parachutist Badge|
|USAF Master Space and Missiles Operation Badge (Old version)|
|Defense Distinguished Service Medal||Distinguished Service Medal||Defense Superior Service Medal|
|Airman's Medal||Defense Meritorious Service Medal||Meritorious Service Medal (***)|
|Air Medal (**)||Aerial Achievement Medal||Joint Service Commendation Medal|
|Air Force Commendation Medal (**)||Air Force Achievement Medal (**)||Air Force Outstanding Unit Award (****)|
|Air Force Organizational Excellence Award||Combat Readiness Medal (*)||National Defense Service Medal (*)|
|Vietnam Service Medal||Southwest Asia Service Medal||Air Force Overseas Ribbon Long Tour|
|Air Force Longevity Medal (***)||Republic of Vietnam Campaign Medal||Kuwait Liberation Medal - Kingdom of Saudi Arabia|
What it means: Um, basically O'Neill is awesome. He's got a lot of medals for defending the nation and I can't tell whether one of the clusters on his Outstanding Unit is silver or not (which would mean he's won it nine times), but either way he's seen a lot action. You can also see he's fought all over the world. Both he and Carter's insignia badges for space and missile are the old versions, which means they were given before 2004. Interestingly, he doesn't have the Air Force Training medal, which is given to everyone upon completion of training. Which means he was trained before Aug. 14, 1974.
Lt. Col. Samantha Carter (circa S10 'Avalon')
|USAF Senior Space and Missiles Operation Badge (Old version)|
|Airman's Medal||Meritorious Service Medal||Air Force Commendation Medal|
|Air Force Achievement Medal||Air Force Organizational Excellence Award||National Defense Service Medal (*)|
|Air Force Longevity Service Award Ribbon (*)||Small Arms Expert Marksmanship Ribbon||Air Force Training Ribbon|
What it means: Sam is the least decorated of the characters, including Major Davis. It makes sense, since she worked mostly in the science divisions and probably didn't see as much action before joining the Stargate Programme. She also hasn't completed an overseas tour.
Lt. Col. Cameron Mitchell
|Command Pilot Badge|
|Distinguished Flying Cross||Purple Heart||Meritorious Service Medal (***)|
|Air Medal(***)||Aerial Achievement Medal||Air Force Commendation Medal (*)|
|Air Force Achievement Medal||Air Force Outstanding Unit Award||National Defense Service Medal|
|Armed Forces Expeditionary Meda||Global War on Terrorism Expeditionary||Air Force Overseas Ribbon - Short Tour|
|Air Force Expeditionary Service Medal||Air Force Longevity Medal (***)||Air Force Training Ribbon|
What it means: Cam got a helluva lot of citations for his whole 'saving SG-1's asses in Antarctica' thing. Interestingly, the first image we see of him is in his dress blues, with all his medals showing. I wonder if that was a subconscious gesture on the writers' part to say 'hey, this guy isn't Jack, but he's awesome'?
Lt. Col. John Sheppard (circa. S3 'Sunday')
(apologies for the crappy cap quality. Due to this, it was hard to tell how many clusters he was wearing, so I've guessed a little.)
|Command Pilot Badge|
|Distinguished Flying Cross (*)||Meritorious Service Medal (*)|
|Air Medal (*)||Air Force Commendation Medal(*)||Aerial Achievement Medal|
|Joint Service Commendation Medal||Air Force Outstanding Unit Award||Air Force Recognition Medal|
|National Defense Service Medal||Afghanistan Campaign Medal||Global War On Terrorism Service Medal|
|Air Force Overseas Ribbon- Long Tour||Air Force Longevity Service Ribbon (*)||Air Force Training Ribbon|
What it means: Basically, John is really talented pilot, which is a surprise to no one. His medals are sort of a mix of O'Neill and Mitchell, which makes sense since his character plays the same role in the series as they do.
Major Paul Davis (circa S6 'Disclosure')
|Meritorious Service Medal|
|Joint Service Commendation Medal (*)||Air Force Commendation Medal (*)||Air Force Achievement Medal|
|Joint Merit Unit Award w/ Gold Frame||AF Gallant Unit Citation||National Defence Service Medal|
|Armed Forced Service Medal||Air Force Overseas Short Tour||Air Force Longevity Medal(*)|
|Small Arms Expert Marksman||Air Force Training Ribbon||United Nations Medal|
What it means: Davis is mostly awarded for non-combat roles, which isn't surprising due to his liaison role. Though he has seen at least some action and is considered an expert marksman with small arms.
So, that's that. Hope this has been educational, or at least interesting for you. Please feel free to correct any mistakes on my part. If you want to link to this please do so. If you know of a place I could post it that might be of use, please let me know.