Cutting out of any portion of an image is known as cropping.

Any part of the image can be selected by cropping.

A preview of the cropped image is visible at the right side.

The process to crop is:

1) Select the part of the image.

2) Select the shape of cropping tool from the menu.

3) Hold shift key and drag to select the marquee to a square or a circle.

4) Hold a marquee from its center, hold down Alt after dragging.

5) Select Image-> Crop menu item.