E–Commerce, also known as e-Business, or electronic business, is simply the sale and purchase of services and goods over an electronic medium, like the Internet. It also involves electronically transferring data and funds between two or more parties. Simply put, it is online shopping as we commonly know it.
CMS stands for content management system which provide faster development of ecommerce website.
WordPress is a CMS, that is “Content Management System”. Drupal and Joomla are CMSes. Others might be considered a “CMS” but that functionality is truly secondary, requires some plugin (some times, a paid plugin).
Drupal and Joomla are possibly better – as development frameworks (second portion of the question) – because they put more attention to being developer friendly.
Overall, WordPress + WooCommerce has “won” in the number of active installations, due to its innate SEO capabilities and amazing amount of free or cheap addons for itself and for WooCommerce.
If we ignore the “CMS” portion and allow the more pure e-commerce solutions, then Magento becomes an high level contender. I call it “high level” because it has (especially in the past) much higher server requirements (memory, CPU etc.) than WordPress. It’s made for large e-commerce websites, whereas WooCommerce is usually used for small and medium e-commerce platforms.
Shopify – one of the most popular platforms to sell products online. It’s a complete, tested and trusted solution that does all the heavy tasks for you. It comes with ready-made themes & multiple languages, abandoned carts recovering, a wide variety of payment gateways and automatic taxes. .
Wix– the platform doesn’t require you to have coding skills and comes with customizable templates. It lets you offer discounts and coupons as well as manage all your content using a single dashboard. The most basic plan is free.
Magento– the solution lets you build branded shops. It also offers a shopping cart system. In contradiction to Wix and Shopify, Magento provides unlimited product attributes. What’s more, it comes with product stock management, email automation, multiple payment gateways and integrations with 3rd party solutions. You can manage various stores using a single solution.
WordPress – one of the most popular and easiest platforms to build websites & blogs. The big plus is that fact that thanks to its popularity, developers around the world are creating more and more WordPress integrations which widen the platform’s possibilities. The basic plan is free.
BigCommerce– the platform allows building and customizing a website to your liking. It comes with ready-made templates and detailed e-commerce analytics. It lets you manage shipping and payments, and even list your products on Amazon.