The difference is:

1. Different appearance. Cabbage and kohlrabi are different in appearance. For example, the leaves of kohlrabi are wrapped around the stem and the bottom is relatively pointed, while the cabbage is wrapped in layers to form a sphere.

2. The edible parts are different. The main edible part of kohlrabi is its rhizome, while the main edible part of cabbage is its leaves.

3. If you have just bought cabbage and kohlrabi, if you cannot finish them, you can store them in a cool, dry place.