For the past few months we’ve been converting WooCommerce widgets in WordPress to blocks. Widgets allow you to add a small feature, such as a paragraph of text, onto your website. 

Widget

Block

On the left we have an example of where a widget can be placed on a website, in this example in a sidebar. Beside it is an example of where a block could be placed. At the moment they can only go in the content area, but the WordPress team is working on ways that they can be placed anywhere on a site.

Read the entire post on Automattic's site