Contentful is an API first content management system, offering four REST APIs for working with your content. Each of these APIs serve a different purpose, so which one to use depends on what you want to do:
The Content Delivery API (CDA), available at cdn.contentful.com, is a read-only API for delivering content from Contentful to apps, websites and other media. Content is delivered as JSON data, and images, videos and other media as files.
The API is available via a globally distributed content delivery network. The server closest to the user serves all content, both JSON and binary. This minimizes latency, which especially benefits mobile apps. Hosting content in multiple global data centers also greatly improves the availability of content.
For more details read the reference guide for the Content Delivery API.
The Content Management API (CMA), available at api.contentful.com, is a read-write API for managing content. Unlike the Content Delivery API, the management API requires you to authenticate as a Contentful user. You could use the CMA for several use cases, such as:
Note: You can also use the Content Management API to retrieve content. But as it's used to manage content, it will retrieve all items (i.e. all localized and unpublished content).
For more details read the reference documentation for the Content Management API.
The Preview API, available at preview.contentful.com, is a variant of the CDA for previewing your content before delivering it to your customers. You use the Preview API in combination with a "preview" deployment of your website (or a "preview" build of your mobile app) that allows content managers and authors to view their work in-context, as if it were published, using a "preview" access token as though it were delivered by the CDA.
For more details read the reference documentation for the Preview API.
The Images API, available at images.contentful.com, allows you to resize and crop images, change their background color and convert them to different formats. Using our API for these transformations lets you upload high-quality assets, deliver exactly what your app needs, and still get all the benefits of our caching CDN.
For more details read the reference documentation for the Images API.