People with healthy eyes have two parts of vision: central vision and peripheral vision which are independent to each other. With peripheral vision, you can see the edges of an object. For example, if you're looking straight ahead at your computer screen, you can also see the keyboard, mouse to the sides and bottom. Without peripheral vision you will only see what faces you directly.
Peripheral vision enables you to see things at the bottom or sides of your central vision. People with poor peripheral vision may be unable to see properly around the edges. These people can only rely on their central vision, just like the vision through a narrow tube.
Peripheral vision, also called side vision, which allow you to look forward and see the sides at the same time.If you have good peripheral vision, you can see objects and movements around you very well.