WordPress Features and Scope

WordPress is an  open source website creation tool written in PHP. In other words most popular blogging platform in the world.

About WordPress

Founded in 2003 by Matt Mullenweg and Mike little
Free and open source CMS
with 1000 of plugins, themes, widgets
74,652,825 and counting WordPress sites in the world

Who use WordPress

https://www.smashingmagazine.com/
http://www.techcrunch.com/
http://www.newyorker.com/
http://www.bbcamerica.com/
http://www.starwars.com/news
http://variety.com/
http://www.sonymusic.com/
http://www.mtv.com/news/
https://www.ebayinc.com/stories/news/?
https://www.bata.com/
http://qz.com/
https://product.espn.com/
http://newsroom.fb.com/

The scope of WordPress

WordPress developer
Theme developer
Plugin developer
WordPress specialist
WordPress designer
WordPress UI designer
WordPress theme designer

Uses of WordPress

Blog
eCommerce website
job board
cms website
small business website
Membership and subscription website
Voting and rating site
Educational website
Forum
Review website
Wiki

How to learn WordPress

To develop WordPress website from scratch needs a good knowledge of HTML, CSS, Javascript and PHP.
Here is some good resource to learn WordPress
https://learn.wordpress.com/
http://wordpress.tv/
http://www.lynda.com/WordPress-training-tutorials/330-0.html
http://codex.wordpress.org/Main_Page
http://www.smashingmagazine.com/category/wordpress/
https://www.udemy.com/courses/search/?q=wordpress

WordPress Developer Salary

http://www.payscale.com/research/IN/Skill=Wordpress/Salary