I have just downloaded and installed Lion from the app store. I would like to make a back-up but don't know where it is on the HD. Can anyone help?

Thanks

When you install it from the App Store, the installer disappears after it does its job. You can make a backup of the installer before you do the install, but as far as I know you can't do so after you install.

When you install Lion (and Mountain Lion later this month) an otherwise invisible Emergency Boot partition is created on your HD. To reinstall Lion, or Mountain Lion, do an "Option Boot" (boot/reboot while holding down the option key) then select the Emergency Boot partition. From there you can run Disk Utility to repair the boot volume, restore the regular boot volume from a Time Machine backup, or download and reinstall Lion/Mountain Lion from the App Store.

Of course if you want to use a belt/suspenders/elastic waistband approach you can always clone the boot drive to another drive using something like Carbon Copy Cloner, Super Duper, or Drive Genius

1. Open App Store.
2. Click on something other that "Purchases".
3. Hold down the Option key, then click on Purchases.

That should again highlight Lion and allow you to (re)download it.

Is that what you seek?

I believe you're allowed to install your App Store Lion on more than one Mac, so if you've got another one, you can d/l the installer again and save the pertinent section; do a Google search for "extract lion installer" beforehand, so you'll know exactly what to do.

The installer can be saved before you run it, but, as tacit has mentioned, it "disappears after it does its job."

Edit: Harv has indicated that you don't need another Mac, so just go with the Google search and follow instructions.

You may install most App Store purchases, including Lion, on up to five computers. The way this is managed is by forcing the install to go through the App Store, including the full downloads. There have been articles and posts on how to save the download — some more successful than others — but in all cases these defeat Apple's management system and an attorney might argue are illegal.

Thanks for the answers, very helpful.