Type

Type is a collection of rules for constructs such as variables and functions. Untyped languages allow any operation to be performed on any data type.

Static vs. Dynamic

static: type is set during compile
dynamic: type is set during execution

Strong vs. Weak

strong: type cannot change during execution
weak: type can change during execution

Language Examples

C: Weak Static
C++: Weak Static
Java: Strong Static
JavaScript: Weak Dynamic
Perl: Weak Dynamic
Python: Strong Dynamic
Ruby: Strong Dynamic

Python Example

Details on Python types can be found here.

Main Python types include:

numerics
- int
- float
- complex
sequences
- list - mutable, defined with [ ]
- tuple - immutable, defined with ( )
- range - defined with range( )
- str - define with “ “ or ‘ ‘
- binary
  - bytes
  - bytearray
mappings
- dict - defined with { }
classes
instances
exceptions

# An example of a type() function return value is: <type 'str'>

# Determine the type of a variable.
variable_example = "A test string."
variable_type = type(variable_example)
print(variable_type)

References