Ruby/C2/Hello-Ruby/English-timed

Time	Narration
00:00	Welcome to the Spoken Tutorial on Hello Ruby!.
00:04	In this tutorial, we will learn
00:06	* What is Ruby?
00:08	* Features
00:09	* RubyGems & Help on Ruby
00:12	Installation
00:13	Running Ruby code
00:15	Commenting
00:16	Difference between puts and print.
00:19	Here we are using: Ubuntu Linux version 12.04 Ruby 1.9.3
00:27	To follow this tutorial, you must be connected to internet.
00:30	You must have knowledge of using Terminal and Text editor in Linux.
00:37	Now I will explain what is Ruby.
00:40	Ruby is an object-oriented, interpreted scripting language.
00:44	It is dynamic, open source programming language.
00:48	It has an elegant syntax that is natural to read and easy to write.
00:54	Now, let us see some features of Ruby.
00:57	Ruby is highly portable.
00:59	Ruby program runs in any operating system.
01:04	Variables in Ruby have no datatype such as in Smalltalk, BASIC or Python.
01:11	It supports automatic memory management.
01:14	Ruby is free format language.
01:17	You can start writing your program from any line and column.
01:21	Ruby is used for developing Internet and Intra-net applications.
01:26	One of the most important features of Ruby is RubyGems.
01:31	RubyGems is a package manager for Ruby programming language.
01:36	It provides a standard format for distributing Ruby programs and libraries.
01:42	You can create and publish your own gems.
01:46	For more information on RubyGems, visit the following link.
01:51	To get more help on Ruby, you can visit the links shown.
01:55	You can install Ruby using the Ubuntu Software Centre.
01:59	For more information on Ubuntu Software Centre, please refer to the Ubuntu Linux Tutorials on this website.
02:07	Other methods for installing Ruby are as shown in this slide.
02:12	Ruby code can be executed in 3 ways-
02:16	* Command line
02:17	* Interactive Ruby
02:19	* As a file.
02:20	We will go through each method of execution.
02:23	First, let us see how to execute the Hello World code from command line.
02:28	Open a terminal by pressing the Ctrl, Alt and T keys simultaneously.
02:33	A terminal window appears on your screen.
02:37	Type the command:
02:38	ruby space hyphen e space within single quotes puts space then within double quotes Hello World and
02:50	press Enter.
02:53	We get the output as HelloWorld.
02:56	puts command is used to print the output on the terminal.
03:00	The hyphen 'e' flag allows only a single line of code to be executed.
03:06	Multiple hyphen 'e' flags can be used to execute multiple line commands.
03:11	Let's try this out.
03:13	Now, press the up-arrow key to get the previous command and
03:18	type: space hyphen e space within single quotes puts space 1+2 and
03:30	press Enter.
03:32	We get the output as Hello World and 3.
03:36	Let's switch back to our slide.
03:38	We will now learn about Interactive Ruby.
03:42	Interactive Ruby allows the execution of Ruby commands with immediate response.
03:48	You can run Ruby statements and examine the output and return values.
03:53	For older version of Ruby, install irb separately.
03:57	Now, let us execute our Ruby code through 'irb'. Go to the terminal.
04:03	Type "irb" and press Enter
04:06	to launch the Interactive Ruby.
04:09	Type: puts space within double quotes Hello World and press Enter.
04:19	We get the output as Hello World
04:22	and we get the return value as nil.
04:25	To exit from irb , type exit and press Enter.
04:31	You can also run Ruby program from a file.
04:34	You can use any text editor of your choice to write the code.
04:39	I am using gedit text editor. Let me switch to gedit text editor.
04:45	Now, type: puts space within double quotes Hello World .
04:54	Let's learn how to add multiple line or block comments.
04:59	Before the puts command,
05:01	type: equal to begin and press Enter.
05:06	equal to begin is used to start the comment.
05:10	Type the comments that you wish to add.
05:13	I will type: "My first Ruby program"
05:20	and press Enter.
05:22	Then type: "This code will print helloworld" and press Enter.
05:30	Now, type: equal to end.
05:32	equal to end is used to end the multiple line comments.
05:37	Comments are useful to understand the flow of program.
05:41	It is useful for documentation.
05:45	Now, let us save the file by clicking on the Save button.
05:50	It is a good practice to save the file frequently.
05:53	The Save As dialog-box appears on your screen.
05:57	Browse the location where you want to save the file.
06:01	On Desktop, I will create a folder named "rubyprogram".
06:06	We will save the file inside this folder.
06:10	In the Name text-box, type the name that you wish to add.
06:14	I will type "hello.rb".
06:17	dot rb extension is given to a Ruby file.
06:21	Then click on Save button to save the file. So, the file is saved now.
06:28	To execute the code, go to the terminal.
06:32	Let's clear the terminal first.
06:35	Make sure that you are in the directory where your Ruby file is present.
06:39	Remember that we are in the home directory. We need to go to the sub-directory rubyprogram.
06:47	To do so, type: cd space Desktop/rubyprogram and press Enter.
07:00	Let's execute the file. Type: ruby space hello dot rb and press Enter.
07:10	We get the output: "HelloWorld".
07:13	Now, let me demonstrate the difference between puts and print statement.
07:18	We will try this out using irb.
07:22	Before that, we need to go back to the home directory. To do so, type "cd" and press Enter.
07:31	Now, type irb and press Enter to launch the Interactive Ruby.
07:39	Type: puts space within double quotes Hello comma within double quotes World .
07:50	Here, comma is used to join the two puts commands together.
07:55	Now, press Enter.
07:57	We get the output Hello World, but on separate lines.
08:03	Now, let's try the same thing with print.
08:06	Press up-arrow key to get the previous command.
08:09	Replace puts with print and press Enter.
08:14	We get the output as Hello World but on the same line.
08:19	The keyword puts adds a newline to the end of the output. The keyword print does not.
08:27	The keyword print outputs only what we have provided.
08:31	This brings us to the end of this Spoken Tutorial. Let us switch back to our slides.
08:37	In this tutorial, we have learnt:
08:39	* About Ruby
08:41	* Installation
08:42	* Execution of Ruby code
08:44	* Adding multiple comments using =begin and =end
08:50	* Difference between puts and print.
08:53	As an assignment,
08:55	write a program to print your name and age.
08:58	We used multiple line comments in this tutorial.
09:01	Try to give single line comment.
09:04	Watch the video available at the following link.
09:07	It summarizes the Spoken Tutorial project.
09:10	If you do not have good bandwidth, you can download and watch it.
09:15	The Spoken Tutorial Project team:
09:17	* Conducts workshops using spoken tutorials.
09:20	* Gives certificates to those who pass an online test.
09:24	For more details, please write to: contact@spoken-tutorial.org
09:30	Spoken Tutorial project is a part of Talk to a Teacher project.
09:34	It is supported by the National Mission on Education through ICT, MHRD, Government of India.
09:41	More information on this mission is available at below link.
09:45	This is Afrin Pinjari from IIT Bombay, signing off.
09:50	Thank you for watching.

Contributors and Content Editors

Devraj, PoojaMoolya, Pratik kamble, Ranjana, Sandhya.np14, Sneha