Pure object-oriented programming language.
Created in 1995 by "Matz".
Open source web application framework.
Mostly new features and improvements.

What is Ruby and Ruby on Rails:
Ruby is a programming language.
Ruby on rails is a framework that is written in Ruby.
Collection of pre-written code to help programmers.
Ruby on rails helps in making website and web application.

Framework:
Collection of program that do something useful which you use to develop some application.
Guides on how to do something.

Downloading and installing:

Variable:
Variable declaration is not needed.

Data type:
Boolean:
Has two values either true or false.
Example: bool=[true, false]
Symbols:
Used to represent objects.
Using symbols instead of string may save some resource.
Hash:
Key value pairs.
Integer:
Can be in decimal, hexadecimal, octal format.
Can be positive or negative.
String:
Represent textual data.
Example: p "Ruby"
Array:
Collection of objects.

Hello world:


Conditional execution:
Checks whether condition is true or not.

If-else:

When:

Loops:
Checking for n no of times.

For loop:

While:

Functions and calling functions:

Mathematical function:

String manipulation:

Input from user:

Replacing input from string:

Writing to file:

Reading from file:

Reading a particular line from a file:

First non-Repeated character:

Highest repeated character of string:

Permutation of string:
%w -> creates array of words.
           Uses spaces to separate each value.
&  -> Used to denote arguments.
Join -> Used to join.

String contains no or not:

Connecting to database:
Downloading devit.
Installing gem.
Adding path of ruby to configure.yml file.