A content management system (CMS) is software designed to make it easier to build and maintain a website. It acts as an interface between the database where your content is stored and the pages that your visitors see — providing an easy way for content to be added to your database and an easy way to retrieve the content and display it on your website.
A website has three parts to it:
1. The CSS stylesheet specifies how different components of your website should be styled — you can define margins and paddings as well as what colors and fonts to use.
2. The HTML code lays out the page. This code indicates where different components are and which styles from the stylesheet should be applied to them.
3. Finally, there is the content itself — the images, headings, and text that appear on your website.
Before content management systems came along, you either needed a database programmer or you had to have a static website with all your content stored in the same file as the HTML that lays out the page. For a small website, this is perfectly feasible. To update the website, you simply update the files and upload them to your server.
However, even with small websites, the person who creates the website is often not the person who needs to make updates to the site. With the content of the website and the HTML code intermingled in the same file, it is difficult to update the content without understanding the code. Due to this, the person who builds the website is often still called upon to make even minor adjustments, long after the website is built. This is not always practical, and so the site is not updated as much as it could be.
A good content management system makes it easier to update the website without any knowledge of the HTML that designs and formats the page. The person who creates the website still needs to know HTML in order to design the page, but the person who updates the website does not. Since the website is easier to update, the site changes more frequently, visitors come back more often, and the site becomes more popular.
A content management system can also turn your website from a one-way flow of information (you write the content, the visitors read it) into a more conversational website. Not only are visitors reading the content you wrote, they can add their own comments into the mix. Your site becomes dynamic, changing even when you are not around.
To illustrate the difference between a static and dynamic website, consider a news website. If, every day, the site had the same articles, you would stop visiting. Why would you read an article you have already read? To keep visitors coming back, it pays to keep the content of your website dynamic. If there is always something new to read, there is more incentive for your visitors to keep coming back.