The Block Editor is used to create new articles (posts) for the Careers, Latest News, Indie Publishing and Case Studies sections of the website.
As the name suggests, the Block Editor treats all your content as individual blocks. Each block can be inserted, rearranged and styled individually.
The Block Editor provides individual blocks for all your common content such as paragraphs, headings, ordered and unordered Lists (i.e. bullet points), quote, images, galleries and any other content. On top of that, the Block Editor also provides additional blocks for easily adding content such as buttons, tables and columns.
The Block Editor allows you to drag-and-drop or use the block mover icons, to rearrange the order of individual blocks. Each block can also be styled individually using the toolbar at the top of block. The types of styles that you can add to a block are dependent on the individual block. A Paragraph Block for example, allows you to change the text size, text colour and background colour, whereas a Heading Block will only allow you to change the level (H2, H3 etc.) and the text alignment.
For more information about the Block Editor see https://en.support.wordpress.com/wordpress-editor/