Python Data Types Tutorial — Learn Data Types in Python

Python Tutorial: Data Types

Every value in Python has a type. Learn them all — strings, integers, floats, booleans, None, and how to convert between them.

Different kinds of data

A name is not the same as an age. An age is not the same as a price. A yes/no answer is not the same as either.

Python uses types to tell different kinds of data apart. Every value has a type, and the type determines what you can do with it.

Twelve steps. Every type, every conversion, every gotcha.

This interactive Python tutorial has 12 hands-on exercises. Estimated time: 20 minutes.

Not all data is the same — In Chapter 2, you stored your name and your age in variables. But did you notice? Your name had quotes around it and you…
str — anything you can read — A `str` (short for 'string') holds text. Your name is a string. An email is a string. A tweet is a string.
int — whole numbers — An `int` is a whole number. No decimal point. Positive, negative, or zero.
float — when you need more precision — A `float` is a number with a decimal point: `3.14`, `99.99`, `-0.5`.
bool — the yes/no type — A `bool` can only be one of two values: `True` or `False`.
None — the 'nothing here yet' type — Sometimes you need to say 'this variable exists, but has no value yet'. That is what `None` is for.
Python figures out the type for you — Here is something wild: you never have to tell Python what type a variable is. Python infers it from the value.
The sneaky "42" vs 42 trap — This is the most common type mistake beginners make. Seriously, everyone does this at least once.
int(), float(), str() — convert between types — You can convert between types:
str() — join text with numbers — You cannot glue a string and a number together directly:
isinstance() — double-check a type — `isinstance(value, type)` returns `True` if the value is of that type — `False` otherwise.
All five types — your turn — Final challenge! No starter code.

Python Tutorial: Data Types

Every value in Python has a type. Learn them all — strings, integers, floats, booleans, None, and how to convert between them.

A name is not the same as an age. An age is not the same as a price. A yes/no answer is not the same as either.

Python uses types to tell different kinds of data apart. Every value has a type, and the type determines what you can do with it.

Twelve steps. Every type, every conversion, every gotcha.

This interactive Python tutorial has 12 hands-on exercises. Estimated time: 20 minutes.

Not all data is the same — In Chapter 2, you stored your name and your age in variables. But did you notice? Your name had quotes around it and you…
str — anything you can read — A `str` (short for 'string') holds text. Your name is a string. An email is a string. A tweet is a string.
int — whole numbers — An `int` is a whole number. No decimal point. Positive, negative, or zero.
float — when you need more precision — A `float` is a number with a decimal point: `3.14`, `99.99`, `-0.5`.
bool — the yes/no type — A `bool` can only be one of two values: `True` or `False`.
None — the 'nothing here yet' type — Sometimes you need to say 'this variable exists, but has no value yet'. That is what `None` is for.
Python figures out the type for you — Here is something wild: you never have to tell Python what type a variable is. Python infers it from the value.
The sneaky "42" vs 42 trap — This is the most common type mistake beginners make. Seriously, everyone does this at least once.
int(), float(), str() — convert between types — You can convert between types:
str() — join text with numbers — You cannot glue a string and a number together directly:
isinstance() — double-check a type — `isinstance(value, type)` returns `True` if the value is of that type — `False` otherwise.
All five types — your turn — Final challenge! No starter code.