Types of DSLR focus

Focus Points - The focus points are the squares or circular shapes shown in the viewfinder, They are shown during Auto Focus to help both you and the camera to focus on a subject, they will at first become apparent when the shutter is pressed halfway down (the time when the lens begins to shift and find a subject to focus on. When attempting to focus the camera shall produce a beep and some of the focus points shall glow red, these lit up focus points indicate what the main subject shall be.

Auto Focus - This focusing method is best used for when you are shooting a moving object and want it to stay sharp and well focused within the viewfinder, the camera focuses on its own so you can spend more time working on the composition and Mise-En-Scene.

Manual Focus - This method is a more hands on approach, using your hands to shift the the focus ring on the DSLR lens until the image is in sharp focus and up to your standards. With manual focus it is also much easier to determine the sharpness of the image using the viewfinder instead of the screen as it avoids any glare, especially during environmental shooting.