The difference between raw_input() and input()

raw_input and input are both built-in functions of Python, which interact with the user by reading input from the console. But their functions are not the same. Here are two examples to illustrate the difference in usage.

Example 1

Python 2.7.5 (default, Nov 18 2015, 16:26:36) 
[GCC 3.4.5 20051201 (Red Hat 3.4.5-2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> 
>>> raw_input_A = raw_input("raw_input: ")
raw_input: PythonTab.com
>>> print raw_input_A 
PythonTab.com
>>> input_A = input("Input: ")
Input: PythonTab.com
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<string>", line 1, in <module>
NameError: name &#39;PythonTab&#39; is not defined
>>> 
>>> input_A = input("Input: ")
Input: "PythonTab.com"
>>> print input_A
PythonTab.com
>>>

Example 2

Python 2.7.5 (default, Nov 18 2015, 16:26:36) 
[GCC 3.4.5 20051201 (Red Hat 3.4.5-2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> 
>>> raw_input_B = raw_input("raw_input: ")
raw_input: 2015
>>> type(raw_input_B)
<type &#39;str&#39;>
>>> input_B = input("input: ")
input: 2015
>>> type(input_B)
<type &#39;int&#39;>
>>>

Example 1 As you can see: both functions can receive strings, but raw_input() directly reads the input from the console (it can receive any type of input). As for input(), it hopes to be able to read a legal python expression, that is, you must use quotes to enclose it when you enter a string, otherwise it will raise a SyntaxError.

Example 2 You can see: raw_input() treats all inputs as strings and returns the string type. And input() has its own characteristics when dealing with pure numeric input. It returns the type of the input number (int, float); at the same time, as shown in Example 1, input() can accept legal python expressions, for example: input( 1 + 3) will return 4 as an int.

Check the python manual and learn that:

input([prompt])

Equivalent to eval(raw_input(prompt))

input() is essentially implemented using raw_input(), just after calling raw_input() The eval() function is then called, so you can even pass an expression as an argument to input() and it will evaluate the expression and return it.

But there is a sentence in Built-in Functions that says: Consider using the raw_input() function for general input from users.

Unless there is a special need for input(), we generally recommend it. raw_input() to interact with the user.