This section of our beginning python training class always stumps students.  Firstly, because they need to know the difference between a function and a method.  Secondly, they need to understand object oriented programming concepts.  Thirdly, they need to realize that python has three types of methods.  Then they need to know how to use each method, which means they need to know the purpose of each method type.  Then they have to understand mutable versus non-mutable types.  The list goes on.  As part of our python tutorial, I hope to shed some light on this confusing topic.

To begin, the difference between a function and a method in python is that a method is defined within a class.  Here is an illustration:

#function

	def greeting():
	                print "Hello, I hope you're having a great day!"

	class HSGPrinter(object):
	                #method
	                def greeting(self): 
	                                print "Hello, I hope you're having a great day!"

As should be obvious, the second definition of greeting is encapsulated within the HSGPrinter class and is , therefore, refered to as a method.

The astute reader will notice that the greeting method contains one parameter named self.  For those who know C++ , Java or C#, self is equivalent to this i.e. it is a reference to the invoking object:

Invoking an external command in Python is a two step process:

from subprocess import call
call(["ls","-1"])

Google is one of the most popular websites in the entire world that gets millions of views each day. Therefore, it should come as no surprise that it needs a strong and reliable programming language that it can rely on to run its searches and many of the apps that Google has created. Because of this, Google uses Python to ensure that every time a user uses one of their products, it will work smoothly and flawlessly. That being said, Google uses Python in a variety of different ways, outlined below.

Code.Google.Com
Since its creation, Google has always used Python as part of its core for programming language. This can still be seen today considering the strong relationship the two have with one another. Google supports and sponsors various Python events, and Python works to better itself so that Google remains on top of cutting edge material. One way that they do this is by working with code.google.com. This is the place where Google developers go to code, learn to code and test programs. And with it being built on Python, users can experience exactly what it is that they should expect once they start using the real site.

Google AdWords
Google AdWords is a great way for people to get their websites out there, through the use of advertising. Each time a person types in a certain string of keywords, or if they have history in their cookies, then they’ll come across these AdWords. The way that these AdWords are broadcasted to online web surfers is built on the foundation from Python. Python also helps clients access their AdWord accounts, so that they can tailor where they want their advertisements to go.

Beets
If you have loads of music, but some of it is uncategorized or sitting in a music player without a name or title, Beets is for you. This Google project uses Python and a music database to help arrange and organize music. The best part about Beets is that even if it doesn’t run exactly the way that you want, you can use a bit of Python knowledge to tailor it to be more specific to your desires.

Android-Scripting
Not only does Google run off Python, but Android also has its own value for the language. Whether you are someone who is just creating your own app for your phone or if you are someone who is looking to create the next app that gets downloaded multiple millions of times, you can use Python and Android-Scripting to create an app that does exactly what you want it to do.

YouTube
YouTube one just started as a video viewer on its own, but is now a billion-dollar company that is owned by Google. YouTube uses Python to let users view and upload video, share links, embed video and much more. Much like Google itself, YouTube relies heavily on Python to run seamlessly for the amount of traffic it gets daily.

Python is not your average coding language. Instead, it is a valuable and integral part of some of the biggest websites in the world, one of which is Google. And the resources listed here are just a fraction of what Google uses Python for in total.

Related:

What Are The 10 Most Famous Software Programs Written in Python?

The Future of Java and Python

Ranking Programming Languages: Which are Gaining Popularity?

Top 10 Software Skills for 2014 and Beyond

Working With Strings In Python

Working With Lists In Python

Conditional Programming In Python

Python is an incredibly powerful and useful computer programming language that many of the biggest websites in the world rely on for their foundation. Python provides reliable results that are functional and involve a variety of dynamic scripted and non-scripted contexts. And because it is free and open source, it has remained a popular choice for a variety of different developers who are looking to build new sites on one of the most reliable languages available. Here is a look at 10 of the most famous software programs that are written in Python and what they do.

YouTube
If you love watching hours of homemade and professional quality video clips on YouTube, you can thank Python for giving you that option. The foundation for Python helped YouTube integrate streaming videos into their pages, as well as the ability to like videos and embed certain information. YouTube is one of the most popular sites on the Internet, and it runs off of one of the most powerful languages in Python.

DropBox
What started as a powerful app, DropBox is now used by a variety of individuals, businesses, companies, organizations and more. This program lets you save files to a cloud-based service, that you can then access from anywhere in the world. With Python at the root of DropBox, there is no longer a need for USB sticks or blank CDs, since you can now save and share everything with your cloud-based account.

Google
It takes a lot of power to be able to handle the most popular search engine in the entire world. That is why Google uses Python for its mainframe foundation, as well as in addition to various apps that it runs in conjunction with the main site. The ease that Google provides for finding certain information, would be impossible without Python at the core.

Quora
Got a question? Ask it on Quora. This site compiles a list of questions and answers that come from a community of individuals. Those questions are then organized by various members of the community, which puts the most relevant information at the top. The creators of Quora, who happened to be former Facebook employees, decided to use Python to help them create the world’s best Magic 8 ball in Quora.

Instagram
If you love taking photos of your food or a new outfit and posting it online for all of your friends to see, you can thank Python for that ability. Granted, Instagram has both a very powerful app and a website, but the latter runs on Python language. The system allows for users to browse, find and post pictures that they like on the site.

BitTorrent
BitTorrent has evolved quite a bit in recent years, but its foundation and earlier years were built on Python. When it comes to one of the largest databases of knowledge, media and content, BitTorrent is the way to go. But you wouldn’t be able to get any of those lectures or other legal stuff that you are downloading from BitTorrent, if it wasn’t for Python.

Spotify
Spotify changed the music game when it allowed you to listen to ad-free music of your choice. This wasn’t a program where you got to select a playlist, but rather full songs that you love, on repeat as many times as you can imagine, if you so desire. But whether you are rocking out to the latest K-Pop song from Psy or a classic jazz tune, you are doing so because Spotify was built on Python.

Reddit
Reddit is one of the biggest open communities on the web. You have a question, want to talk about something in specific, or find tons of information regarding a particular topic, you can just look on Reddit. The site relies on Python to help them store user names, categorize subreddits, upload links to GIFs and, of course, award gold to valued posters.

Yahoo Maps
Much like Google, Yahoo also uses Python for a variety of different resources. Most valued may be Yahoo Maps. The API and programming behind the maps program, which is built with Python, allows for users to find locations, get directions and even find reviews about local places.

Hipmunk
If you love to travel, you have likely come across Hipmunk. And while the site lets you save money on booking your itinerary through Hipmunk, it is Python that keeps everything organized. Python also helps sort the best discounts and rates, so you can get the best packages available.

Python is an incredibly powerful tool for web development. More and more sites rely on it, including 10 of the most powerful sites in the world that are listed here.

Related:

Current Active List of Organizations that use Python 

Working With Lists In Python