What is binning and what is the advantage of binning?

Binning is a read-out method where the charge from more adjacent pixels are added together and read out as a single pixel. In horizontal binning adjacent pixels in the same line are added together. In vertical binning adjacent pixels in the same column are added together. In some JAI cameras, a combination of both is used. The advantage of binning is a higher read-out frame rate, and a higher sensitivity. With both Horizontal and Vertical binning, the image aspect ratio is correct. The resolution for a two-to-one binning will be 50%.