What is the difference between unstable and stable IP address?

What is the difference between unstable and stable IP address?
Does it affect the internet connection speed?
This is what I don't get, why should I get an unstable IP address whilst my brother gets a stable one? I told him that I do not want unstable IP address and he told me: that's fine, and that he will have the unstable IP address since it's better. But when we got the new part of router extension, I found out that mine is on the unstable IP address, what the eck? Stupid brother just wanted a stable IP address for his game.

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Today, I went into university for about 10.30. A came too, supposedly for her other friend F. I was busy just correcting and trying out certain things on my Python application. However, I didn't know how to make the program check through certain data in the database before allowing it to be accepted as a value.

I tried to make it as a variable the values, but since there is more than one value in the variable, it didn't allow me to check one value against the variable. It was an error as it kept saying it's not integer, aww.

Stayed until 7pm doing the coursework again, was so hungry. Stayed up all night doing the coursework with only half an hour sleep because of me nodding off. So in fact that this is sort of posted on Wednesday when it's suppose to be for Tuesday, lol!