Lock-free and wait-free algorithms

Lock-free and wait-free algorithms are ways to make sure different computer processes can work together without getting in the way of each other.

Okay, let's pretend you have two toys you want to play with at the same time. You really like playing with both toys, but you have to share them with your friends. This is kind of like how different computer processes have to share resources like memory or the same file.

One way to share the toys is to use a system where only one person at a time can play with a toy. So you and your friend would have to take turns with each toy, and while one of you is playing with a toy, the other one can't use it. This is like how regular computer processes work with locks - only one process can use a resource at a time, and the others have to wait in line until it becomes free.

However, there's another way to share the toys - you can both play with different toys at the same time without getting in each other's way. So you might play with the car toy while your friend plays with the ball toy. This is like how lock-free and wait-free algorithms work.

With lock-free algorithms, different processes can access a resource at the same time, but they have to take turns doing it. So if you want to use a resource, you have to check if it's being used by another process, and if it isn't, you can use it. But if it is being used, you have to wait until it's free before you can use it too.

With wait-free algorithms, different processes can access a resource at the same time without waiting for each other. So you can use the car toy and your friend can play with the ball toy, without having to take turns or wait for the other person to finish.

Overall, lock-free and wait-free algorithms are like sharing toys - you can either take turns or play with different toys at the same time. It's just a way to make sure everyone can use the resources they need without getting stuck waiting for other processes to finish using them first.