In Python, an integer is a whole number, positive or negative, without decimals, of unlimited length. Integers are one of the three numeric types in Python, along with float and complex numbers. Integers can be created by assigning a value to a variable, and the type of any object in Python can be verified using the type() function. Integers can also be converted from one type to another using the int() method. Python 3 supports integers of any length up to the memory limit of the computer.