The lower the f-stop number, the larger the aperture, the more light enters the camera. So, f/1.4 means the aperture is pretty much all the way open, and lots of light is entering the camera. You might be wondering why f-stops are displayed using decimals (e.g., 1.4, 2.8, and more).

Which aperture is largest?

The specifications for a given lens typically include the maximum and minimum aperture sizes, for example, f/0.95–f/22. In this case, f/0.95 is currently the maximum aperture (the widest opening on a full-frame format for practical use), and f/22 is the minimum aperture (the smallest opening).

Is 1.8 or 2.2 aperture better?

f/2.2 is likely a better quality lens (less aberrations, a wide aperture becomes difficult), and is smaller, lighter, and less expensive, but f/1.8 opens wider to see more light in a dim situation.