As almost ANY Digital camera would be...
folder contains your photo's taken from your phone..
Media folder would be any photo's you placed yourself...
But Generally DCIM
is your Main folder...
This is after you Set your Photo to Mass Storage.
Samsung Galaxy S Exact Instruction to Confirm and explain Below;
Plugging in Samsung Galaxy S:
Step 1. Settings > [Scroll to the Bottom] About Phone > USB Settings > Select "Mass Storage" [This should be the one with Green Dot, if it isnt, Select it] - Once this is done Exit to home screen (Press the back button until back to main screen with background - Not necessary but no point having it on setting screen)
Step 2. Plug in Device to Computer via USB Cable - XP / Vista / 7 works good - Mac Tiger or up Works good too
Step 3. Use the Top Status Bar and pull it down.
Step 4. Select the Status that mentions "USB Connected
Step 5. A pop up window will show up. Press - MOUNT
Your Device SD is now mounted to PC and is acting as a Mass Storage Removable Disk.
My Computer > Removable Disk X (where X is the next letter available to name a drive)
There you'll find your DCIM folder Plus other folders.
Drag / Copy / Move - Any files you need
Once Done Follow these Steps:
Removing / Unplugging Samsung Galaxy S:
Step 1a. Close the Removable Disk Folder and Make sure No Files is Transferring and/or make sure no program (including windows) is talking to the Removable drive.
Step 1b. You can Safely remove your Drive from your computer. But this step isn't necessary.
Step 2. Open your Status Bar on your Phone on the top screen by pulling it down
Step 3. Click on Status bar "Turn off USB Storage
Step 4. a Pop up will show up. Click "Turn Off" - This will Dismount your removable Drive from your computer.
Step 5. Unplug your USB cable.
You Are Done.
You have another Option. Download Samsung Kies. from Samsung Official Website.
Support for that program is offered by 1-800-SAMSUNG. Although I personally ill advise using that program unless you need to update your phone or back up Device Memory Contacts. That program has known issues and Samsung has taken it off there website numerous times to do "Patch updates" on it to prevent it from crashing.
Hope This Helps.