It's their version of Sunday.
Yes and no. Shabbat is our weekly day of rest, but unlike for most modern-day Christian denominations it comes with a lot more attached. In particular restrictions: No use of electricity except what we leave on from before it starts, (which means no computers, no cars, no phones, no TV). Other restrictions include no lighting fires, no cooking, no leaving the city in which we are located beyond a certain distance, and no carrying things into and out of buildings unless something called an eruv is constructed. Most non-Jewish (and many Jewish) sources will extremely inaccurately describe all of the above as "no doing work".

We drink wine and eat challah before each meal, and just generally stay home and spend time with the family. In addition, there's the general attitude of resting. We can warm up food that's already cooked using a hot plate, which is where the food I made sat.

So the verdict?

The chicken tajine came out fantastic - far better than the last time I made it (when the water didn't evaporate fully) because I actually had the right kind of pot, so it was absolutely worth it. The rice also came out fantastic - it always does. And the mafrum was terrible. Far too much work for something that looked like it wasn't really going to be worth it, and I didn't cook it enough afterwards (not enough time before shabbat started) so it tasted terrible. I'm going to put it on the fire tonight and see if it turns out good, but either way I'm not making it again.