automatic mode: Automatic mode practically do everything for you.
portrait mode: Portrait mode automatically selects a big aperture.
macro mode: Macro mode is good for shooting small objects like flowers and insects.
landscape mode: Landscape mode does the opposite of portrait mode, it sets a small aperture.
sports mode: Sports mode is best for shooting moving objects.
night mode: Night mode is best for shooting it low light.
movie mode: Movie modes is good for capturing moving objects.
aperture priority mode: AV mode lets you chose aperture while the camera choses other settings.
shutter priority mode: TV mode lets you chose shutter speed while the camera choses other settings.
program mode: Program mode is similar to Auto but gives you a little more control over some other features including flash, white balance, ISO etc.
manual mode: Manual mode give you full control over the camera.