Why are Python strings immutable? Best practices for using them

Question

1. What are the design reasons of making Python strings immutable? How does it make programming easier?
2. I\'m used to mutable strings, like the ones in C. How am

Answer 1

Immutable strings makes programming much easier, which is why C# and Java use them too.

Had strings been mutable, you would not be able to trust any externally-provided string, since a malicious caller could change it underneath you.
It would also make multi-threading much more difficult.