Why do Jews remember and celebrate Exodus?

No particular reason. It just seems like a good time of the year to take time off

from work, get together with family, have some great meals and a lot of wine.

Very much like Christmas and Easter, which are likewise vestiges of ancient

traditions based on historically uncorroborated folklore, and which likewise

have little or no relevance or usefulness in these modern times.

The traditional viewpoint is that it is a specific commandment in the Torah to

remember the Passover, and another specific commandment to tell ones children

about it. There are several reasons for this. However, the primary reason given is

that this is when G-d made and "appearence" so to say in the world which

showed that he was not only the creator of the world, but that he is involved in

the daily workings of the world continuously. This was the event that was the

beginning of the Jewish people as a nation and the giving of the Torah on Mount

Sinai, eventually culminating in the Israelite nation entering and settling in the

land of Canaan (Israel).