Iphoto - how are the photo files managed and stored ?

Question

I am one of those who migrated from the PC to this wonderfull world of the Mac. So please excuse my PC based way of thinking. 
I have many thosands of photos, (aprx. 8,000 +++ )
I used to organized my photos on an external hard disk and and I would create folder that would hold a group of photos; for example (A folder labeled "Vacation on New York" will hold all the photos for that event)
Now on my iMac, I could import all the photos on that folder and create an event on iphoto called "Vacation on NY"
The only question I have is where do those file phisically go to?  Where are those  files with their names and extensions?  What folder or directory do they go to once I import them into iphoto?
I need to know this so that I could get a back up and know how to manage the files.
Also...
I would like to know how can I close all events at once.
Thank you in advance for all the explanations......

Answer 1

The files are copied into the iPhoto Library which is in your Pictures Folder.
Most Simple Back Up
Drag the iPhoto Library from your Pictures Folder to another Disk. This will make a copy on that disk.
Slightly more complex:
Use an app that will do incremental back ups. This is a very good way to work. The first time you run the back up the app will make a complete copy of the Library. Thereafter it will update the back up with the changes you have made. That makes subsequent back ups much faster. Many of these apps also have scheduling capabilities: So set it up and it will do the back up automatically. Examples of such apps: Chronosync or DejaVu . But are many others. Search on MacUpdate
By way of explanation:
The iPhoto Library  is a Package File. This is simply a folder that looks like a file in the Finder. This is to protect the iPhoto library because many users were inadvertently corrupting their library by browsing through it with other software or making changes in it themselves.
Want to look inside?
Go to your Pictures Folder and find the iPhoto Library there. Right (or Control-) Click on the icon and select 'Show Package Contents'. A finder window will open with the Library exposed.
Standard Warning: Don't change anything in the iPhoto Library Folder via the Finder or any other application. iPhoto depends on the structure as well as the contents of this folder. Moving things, renaming things,, deleting them or otherwise making changes will prevent iPhoto from working and could even cause you to damage or lose your photos.
To use an editor with iPhoto: You can set Photoshop (or any image editor) as an external editor in iPhoto. (Preferences -> General -> Edit Photo: Choose from the Drop Down Menu.) This way, when you double click a pic to edit in iPhoto it will open automatically in Photoshop or your Image Editor, and when you save it it's sent back to iPhoto automatically. This is the only way that edits made in another application will be displayed in iPhoto.
To use the files in other apps, upload them etc
There are many, many ways to access your files in iPhoto:   You can use any Open / Attach / Browse dialogue. On the left there's a Media heading, your pics can be accessed there. Command-Click for selecting multiple pics.
(Note the above illustration is not a Finder Window. It's the dialogue you get when you go File -> Open)
You can access the Library from the New Message Window in Mail:
There's a similar option in Outlook and many, many other apps.  If you use Apple's Mail, Entourage, AOL or Eudora you can email from within iPhoto.
If you use a Cocoa-based Browser such as Safari, you can drag the pics from the iPhoto Window to the Attach window in the browser.
If you want to access the files with iPhoto not running:
For users of 10.6 and later:  You can download a free Services component from MacOSXAutomation  which will give you access to the iPhoto Library from your Services Menu.
Using the Services Preference Pane you can even create a keyboard shortcut for it.
For Users of 10.4 and 10.5 Create a Media Browser using Automator (takes about 10 seconds) or use this free utility Karelia iMedia Browser
Other options include:
Drag and Drop: Drag a photo from the iPhoto Window to the desktop, there iPhoto will make a full-sized copy of the pic.
File -> Export: Select the files in the iPhoto Window and go File -> Export. The dialogue will give you various options, including altering the format, naming the files and changing the size. Again, producing a copy.
Show File:  a. On iPhoto 09 and earlier:  Right- (or Control-) Click on a pic and in the resulting dialogue choose 'Show File'. A Finder window will pop open with the file already selected.    3.b.
b: On iPhoto 11 and later: Select one of the affected photos in the iPhoto Window and go File -> Reveal in Finder -> Original. A Finder window will pop open with the file already selected.