A vise is a special tool that helps hold things really tight when you need to work on them. It's kind of like a super strong hand that grabs onto objects and doesn't let go until you want it to.
Imagine you have a really special toy that you want to fix. But it's small and you can't hold it very well with just your hands. So you ask the vise for help. The vise has two parts - a stationary part and a moving part. The stationary part is like a big metal mouth that doesn't move. The moving part is like a big metal jaw that can open and close.
First, you open up the vise by turning a handle or a screw. The moving part moves away from the stationary part, just like when you open your mouth wide. Then, you put your special toy inside the vise's mouth. Now, you can start fixing it because the vise is holding it really tight!
Once your special toy is in the vise, you can close it by turning the handle or screw the opposite way. The moving part comes back towards the stationary part, just like when you close your mouth. It grips the toy tightly so it doesn't move. Now you have both hands free to fix your toy!
The vise is very strong and won't let go of your toy until you're done and tell it to. That's why it's such a helpful tool. When you're finished fixing your toy, you simply turn the handle or screw the right way to open the vise again. Then you can take your toy out and it will be all better!
You can use a vise for lots of different things, not just toys. If you want to saw a piece of wood, you can put it in the vise and it will hold it steady for you. Or if you want to hammer a nail into something, you can use the vise to hold the thing so it doesn't move while you hammer.
So a vise is like a strong tool that holds things really tight and helps you work on them without them moving around. It's like having an extra strong hand that holds onto things for you!