# 7.5. Strings are immutable¶

It is tempting to use the operator on the left side of an assignment, with the intention of changing a character in a string. For example:

The greeting string is an example of an object and the character you tried to assign is an example of an item. For now, think of an object as a special virtual construction. Objects have special properties. Strings, for example, are objects that hold a sequence of characters. An item is one of the values in a sequence.

The reason for the error is that strings are immutable, which means that you can’t modify an existing string. The best you can do is create a new string that is a variation on the original:

This example concatenates a new first letter onto a slice of greeting. It has no effect on the original string.

Or, you can reassign an existing variable to a completely new string:

This example assigns the greeting variable to represent a new string object. The old string object is deleted in the process.