Computer Vision in the field of AI enables computer systems to deduce meaningful interpretations from images or any other visual STIMULATION and take ACTION based on that input. AI gives the system the ABILITY to think, then computer vision gives the system the ability to observe. Computer vision is very much similar to human vision.

Pattern recognition is the foundation of today's computer vision algorithms. We train computers on a vast amount of visual data—images are processed, things are labeled, and patterns are found in those items. For example, if we submit a MILLION photographs of flowers to the computer, it will analyze them, find patterns that are common to all flowers, and produce a model "flower" at the end of the process. As a result, every time we submit them photographs, the computer will be able to precisely recognize whether a certain image is a flower. Computer vision is can be witnessed in many areas of our lives. 

For example- Content organization in Apple Photos, Facial Recognition systems, self-driving CARS, augmented reality, etc. use computer vision.