A WordPress theme provides all of the front end styling of your WordPress site.

What is a WordPress Theme? from iThemes.com on Vimeo.

WordPress uses themes to control the look and presentation of your site. You can  quickly change themes and change the entire look of your site, while still maintaining the underlying WordPress software that powers your site. 

WordPress themes are kind of like how a new outfit can give you an entirely new  look. But themes go even deeper than just the design. They control the layout and functionality of your site as well. You can create different layouts for different types of content with a theme. 

You can change the entire look of your site without ever changing the content or  back-end structure. A few clicks of the mouse and you can add a new theme and have an entirely new look. It can make updating your site and keeping things current a much quicker and simpler process.

Themes come in all types and varieties, including free and premium themes. You  can also customize a theme to make it your own.

Most WordPress themes provide:

  • The overall design or style of your site
  • Font styling
  • Colours
  • Widget locations
  • Page layouts (or templates)
  • Styles for blog posts and blog archives
  • Additional stylistic details

Important note: Keep in mind that we are only talking about existing (free and  premium) themes, custom developed themes can have added functionalities, features and custom code, meaning that switching to a different theme, there can be some functionalities that can stop working properly or simply won’t appear on that new installed theme.