It's a database, and whether or not you need it depends on why it's there. Some program may depend on it. You could uninstall it and then see what breaks, but longer term you need to pay more attention to what you're installing on your computer.
Hello, my computer has been very slow and I think it may be because of something called mysqld which is taking up 78% of my CPU usage. What is this, and do I need it?
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