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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, RubyGems & Help on Ruby
00:12 Installation, Running Ruby code
00:15 Commenting, 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 the knowledge of using Terminal and Text editor in Linux.
00:37 Now, I will explain you 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 a 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 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 , Interactive Ruby and
02:19 As a file. 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: 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 a 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 the return values.
03:53 For older version of Ruby, install the 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 the 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 the 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 as "HelloWorld".
07:13 Now, let me demonstrate the difference between puts and print statements.
07:18 We will try this out using "irb".
07:22 Before that, we need to go back to our 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 the 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 slide.
08:37 In this tutorial, we have learnt:
08:39 About Ruby, 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:
09:30 Spoken Tutorial project is a part of the 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 the 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