What does the guitar muffler do?

I’m a beginner of guitar. I want to ask what the guitar muffler is for. If the muffler is on the guitar, will the popularization of song talk be changed?
As the name implies, it is variable. In principle, the length of the original guitar string is shortened to make the string more tunable. The empty string may have been G-tone, and with the muffler, the string becomes shorter and the empty string becomes higher. According to the actual situation, some songs are high-profile. They need to add a single clip before they can play. Of course, they need not change. But there are normal spectra, which will change with the addition of clips. Personally, I advise beginners not to use this stuff first. It is more important to practise basic skills steadily than anything else. When you don’t feel like it’s too much trouble, use it again. What’s your use for it now? It’s not clear what the difference is between using and not using it, which means you don’t need it at present.