Making inside or edges blur of a photograph

Guys you may have noticed that in many graphic design designer draw an edge blur effect that increase the attraction of a photo. Follow the instructions given below because you are gonna learn to do so............

step1: 1st open any image you like. I took this photo from vista wallpaper

step2: Now create a new rectangel with Rectanguler marquee tool within the photo as you like.

step3:Now go to select> feather>radius=20 pixel

step4:Now press the Ctrl+Shift+I and now press the 'Delete' key on your keyboard .

and here is the final result

now if you want to make inside blur then return to the select>feather >radius=20 pixels

Than

ctrl+i and press "DELETE" key .

Now see the result.

You can bring variance in selection tools or in feather radiuses size.