Why does uncommitted change in a branch affect the master branch?

Question

I am new to git and I am trying to experiment with it to understand the concepts particularly the branching and merging.

So here is my set up,

I have a master br

Answer 1

In Git or any version control system all the merge operations are to be done on the local machine itself. So, if you have any uncommitted changes on any branch so that they don't get lose/unnoticed they are merged with branch just switched/new checkout. Your changes will always be there unless you use git push. Ofcourse, there could have been a reverse case as well, but it is often more beneficial for the programmer.