transferring files and apps from 24 inch imac to 27 inch imac

I am considering purchasing the new 27 inch imac but do not know how to transfer all apps, files, settings etc; from my current 24 inch imac.
Can this be done in a single move or do I have to go back to original installation discs/downloads.

I have an external 1tb disk for backup using Time Machine so could I transfer using this.

You would transfer using your external drive.

When you first turn on a new Mac it will ask if you want to import from a backup - have your TM backup disk connected and ready to go.

Thank you ChrisMan287 and bobtomay - much obliged - just have to save up the £sss now for the 27 inch.

Transferring from mac to mac

bobtomay said:

When you first turn on a new Mac it will ask if you want to import from a backup - have your TM backup disk connected and ready to go.

Click to expand...

Just a further thought - I have Lion OS installed on my 24' - I presume a new 27" will have Mountain Lion pre-installed - would this cause a problem when I am importing my back-up - or does the import only involve apps, files, settings and not the OS?

techymac said:

...does the import only involve apps, files, settings and not the OS?

Click to expand...

Yes..

Thank you bobtomay - much appreciated