When released, it will replace the current post editor, which includes a visual mode with real-time previews and a text editor that displays the HTML code of the post content. Gutenberg is the first revamp of the WordPress post editing experience since the inception of the content management system, and it will introduce significant changes to how posts and pages are edited in WordPress.
Gutenberg is built around the concept of blocks. Each element in the content of a page or post is a block – paragraphs of text, images, videos, blockquotes, lists, galleries, tables, and so on. Blocks can be added, deleted or moved around in the content, and each block has settings unique to the block type. In the image block, you can select which image to display, how to align it, and edit the caption. In the table block, you can add and delete table rows and columns.
If you want to reuse a certain block, you can save it as a shared block, after which you can add it with the click of a button on other posts and pages. You can try the editing experience through the Gutenberg test page.
The default blocks included with Gutenberg have the same capabilities as the formatting options currently included in WordPress, along with a bunch of new features that give users more control over the end result. The contextual settings for each block means that Gutenberg can provide additional settings without making the interface feel cluttered.
The big difference between Gutenberg and the current editing experience in WordPress, except the overall improvements in user experience, is that Gutenberg is built to be flexible and extendible so themes and plugins can add their own blocks with custom functionality and layout. For a company page, for instance, a theme could include a “Employee” block that can be added for each employee that should be listed on the page. Long term, the change to the block paradigm holds the promise of more dynamic page layouts across the board for WordPress websites.
In the short term, Gutenberg is still under development. We don’t have a date for when it will be added to WordPress core. When that time comes, the current text editor and visual editor will be replaced by Gutenberg. WordPress users who want to retain the existing editing experience can install the Classic Editor plugin, which restores to old post editing experience to WordPress. Installing it is probably not a long-term solution, though. Once Gutenberg is released, it will be here to stay, and retaining the classical editor will not be feasible long-term.
The WordPress community is big. It’s unavoidable that the transition from the classic editor to Gutenberg will have its speed bumps, as many existing WordPress sites built on top of the existing structure will break once the Gutenberg update starts rolling out. Still, after the dust settles, the overall improvement to the editing experience in WordPress will be worth it.