What is photo stitch?

Photo stitch is the process of stitching photos to a wide angle photo or panoramic photo.The photo stitch software is used to combine multiple photos with overlapped fields together into a whole piece of 360 Panoramic photo. Usually, the photo stitch process inner photo stitching software are mainly divided into 3 stages:
The first stage is image registration: the photo stitch software searches for multiple overlapping pixels between photos to find matching points(matching features)
Second, to calibrate or optimize the optical defects between images, such as the exposure differences, distortion etc..
At last, blending, it's the process to merge and remap the images into a final seamless panoramic photo.
The panoramic photo stitched by photo stitch software can show 360 degree field of view of the location, which is usually used for showing real estate properties, events, and tourism, it is also widely used for website design, multimedia design and even the crime scene investigation.

Source:http://www.easypano.com/photo-stitch-software.html