Welcome to the Daily Halacha. A question came up on Shabbat: Is one allowed to move a garbage can to collect garbage, or throw out the garbage on Shabbat? Why is it even a question? A person has to be careful because it is Muktzeh. Muktzeh on Shabbat means certain items that Chachamim (Sages) made are not allowed to be touched or moved on Shabbat, because that might lead us to disrespect Shabbat, disregard Shabbat, and not appreciate it and actually live the moment of Shabbat.
The whole point of Shabbat is for us to relax. What does relax mean? What did Hashem mean when He said Shabbat has to be oneg? Shabbat has to be enjoyable, has to be bimenuchat hanefesh, has to be with calmness, has to be relaxed. What does that mean? Relax means you let your neshama (soul) connect with Hashem through learning a lot of Torah on Shabbat, through praying, and through singing Shabbat zemirot (Shabbat songs). Also, having very good food is very important. It's very important on Shabbat because it's a way to get us to relax in order to connect to Hashem better through tefillah, through praying, through learning Torah. So the point of Shabbat is to connect to Hashem.
So, Chachamim, in a nutshell, I'm telling you something that's very big, a very big sugya (Talmudic discussion): a lot of dapim (pages) and Gemara, different pesukim (verses) and the Nevi'im, a lot of halachot (laws) and Shulchan Aruch. This is a lot of Torah, and I'm telling you quickly. So Chachamim made something called Muktzeh, asur b'Shabbat (prohibited on Shabbat), which means that a person is not allowed to touch certain items because it might lead to overusing those items on Shabbat, and then you're going to forget it's Shabbat. You're not going to appreciate Shabbat; you're going to be too busy walking around with those items, playing with those items, busy with them, or you might carry them in a place without an eruv (an enclosure permitting carrying on Shabbat). So there are certain tools on Shabbat that are considered Muktzeh. Garbage, garbage cans, and garbage bags are Muktzeh b'Shabbat.
Now, what does that mean? Does that mean a person cannot throw out his garbage on Shabbat? The answer is that if a garbage bag gets piled up all the way to the top so that it starts smelling in the kitchen—or even before it starts smelling, if it is already overpiling, which is disgusting to everyone—only then can a person pick up the bag and chuck it in the garbage outside, if he has an eruv right next to his house where he can carry the garbage bag. Otherwise, you're not allowed to take out the garbage because the garbage is Muktzeh.
The only reason you can take out the garbage when it's full is that, even though it's Muktzeh because it's a garbage bag, it might ruin your feeling of Shabbat: it's going to smell, and it's uncomfortable to have the garbage full in the kitchen. Then the Chachamim gave us a heter, a leeway, to take out the garbage bag. But if the garbage bag is not full and it can get filled up more, and it doesn't stink up the house yet, then a person halachically cannot throw out the garbage bag. It's a very, very important halacha (Jewish law) to know. Muktzeh applies a lot on Shabbat, and it's very worth it for a person to learn those halachot.