As of late December of last year the top 5 CMS, in order, were WordPress, Wix, Squarespace, Joomla!, and Shopify.
WordPress.org is the most popular CMS, with 27 million live websites, 54% CMS market share, and 36% of the entire Web. This is not without reason. The WordPress CMS is free and open source, but can be deployed by someone who does not know how to code, though I wouldn’t expect a complete technical beginner to deploy it successfully. My mother, for instance, could absolutely make posts and pages on a WordPress site, but she’d need my help to deploy WordPress on the site and set up the theme and plugins.
WordPress has many themes, and all of them are customizable, either through the “additional CSS” option or by tweaking the theme’s style sheet itself. WordPress is mobile friendly and responsive.
WordPress is great for blogging, but can be used for almost any website of up to medium size and complexity. There is a robust ecosystem of plugins, both free and paid, to do anything you want a website to do. WordPress.org is on-premise software. It must normally be downloaded as an archive from the wordpress.org website, then uploaded and unzipped to your domain via the FTP offered by your hosting provider. Some hosting providers have work-arounds to help you with this. Note that WordPress.org is distinct from, and more robust than, WordPress.com, which is not open source, and sill focused strictly on blogging.
Wix is a paid website builder that’s deployed on 3.8 million websites, capturing 7.8% of the CMS market share. I have not personally used Wix yet, so this is a review based on other reviews, not personal knowledge. Wix is paid, with the cheapest plan starting at $13/month, but this is an all inclusive price and . Wix is marketed to small businesses that need a website, but don’t have anyone on staff who’s capable of deploying WordPress, and who don’t want to hire (or can’t afford) a freelance web designer like me. Wix is simple enough for a complete beginner to figure out and use. They have a large number of very good looking, responsive templates, but you aren’t going to get behind the scenes and tweak them like you can with WordPress.org. Wix appears to be a software-as-service platform. They offer a free, non-time-limited option, but your site will be at their domain and host their adds.
Squarespace is a drag and drop CMS that is offered as software-as-a-service. It is attractive, and very easy to learn, but hard to use if your computer or your internet connection is slow. The Robins Hunter Museum website was built in Squarespace. It is paid and closed source, and unlike Wix, they don’t offer a feature-limited free option, just a time-limited free trial. Squarespace is probably the easiest to use CMS that I have personally encountered, provided that your computer and internet are both reasonably fast. Reviewers note that their template selection is a bit more limited than Wix or WordPress, with a minimalist aesthetic involving significant white space. Squarespace’s eCommerce options were perfectly suited to the museum’s needs. They do allow you to insert custom HTML blocks and add custom CSS code into your site. Squarespace powers 1.8 million websites, 1.4 million of them in the US, and has a 4% market share.
Joomala! is an advanced CMS that lets you do more than you could do with WordPress or any other popular CMS, but it is also harder to use. Joomala powers 1.8 million websites worldwide, but only 400,000 of them are in the United States, and it has a 3.5% market share. My experience with Joomala is limited and consists only of classroom exercises, but I hope to change that this fall. Literally any kind of website can be built with Joomala, but it is better for more complex web sites, including apps, and a bit worse for blogs. Like WordPress, Joomala is free and open source, and like WordPress, you must download it, upload it, unzip it, and install it on your server. It is a bigger file than WordPress if I recall correctly.
Finally, the fifth most popular CMS, and the most popular “specialized” CMS is Shopify. It is a closed-source, “software as service” CMS that is specialized for the creation of Amazon-like stores and nothing else. SSL is built in, which is very important given its purpose. I have no personal experince with this CMS, but it powers 1.1 million websites, though that amounts to less than 1% of the market share. But that’s a bigger share than Moodle or any other specialized CMS.