How to Run First Program in Python

When you are a first-time learner of Python, the below commands you can try on windows Python-interpreter. Python is a powerful and multipurpose language.

At the highest level, Python is an interpreted language. And you don't need declarations for:

1. Variables
2. Methods
3. Parameters
4. Functions

You don't need a compiler. During the run-time, the Python interpreter validates the code and shows-up errors.

How to Run First Program in Python.

$ python        ## Run the Python interpreter
Python 2.7.9 (default, Dec 30 2014, 03:41:42) [GCC 4.1.2 20080704 
(Red Hat 4.1.2-55)] on linux2Type "help", "copyright", 
"credits" or "license" for more information.
>>> a = 6       ## set a variable in this interpreter session
>>> a           ## entering an expression prints its value
6
>>> a + 2
8
>>> a = 'hi'    ## 'a' can hold a string just as well
>>> a'hi'
>>> len(a)      ## call the len() function on a string
2
>>> a + len(a)  ## try something that doesn't work
Traceback (most recent call last):
  File "", line 1, in 
TypeError: cannot concatenate 'str' and 'int' objects>>> 
a + str(len(a)) 
## probably what you really wanted
'hi2'
>>> foo         ## try something else that doesn't work
Traceback (most recent call last):
  File "", line 1, in 
NameError: name 'foo' is not defined
>>> ^D          ## type CTRL-d to exit 
(CTRL-z in Windows/DOS terminal)

Sources

1. How to execute a script in Python