What mutable data types do you know in programming?

Mutable (changeable) data types in programming are those whose contents can be modified after the object is created.

In Python, mutable types include:

• list — lists, elements can be changed, added, removed
• dict — dictionaries, key-value pairs can be modified
• set — sets, elements can be added and removed
• bytearray — a mutable array of bytes

Example:

my_list = [1, 2, 3]
my_list.append(4)  # list has changed

my_dict = {'a': 1}
my_dict['b'] = 2  # dictionary has changed

Unlike them, types such as int, float, str, tuple are immutable.