Neo is a Craft CMS field type that builds upon the concept of the Matrix field type with a number of very useful features. Neo has been carefully crafted (pun intended) to ensure it matches the look and feel of Craft.
In contrast to the Matrix field, block types are built using existing fields.
Sometimes block types require having a lot of fields. Using the field layout designer, you can organise fields into tabs, much like when creating entry types.
And sometimes you end up with many block types. Adding groups allows you to organise your block types into drop down menus.
Neo has the ability to set a maximum count on individual block types.
Let block types have the ability to contain child block types. You can filter what blocks are allowed within others, as well as set whether a block type can only be a child of another.
A copied block can be pasted anywhere within its field that allows that particular block type to exist. Neo copies/pastes a block with descendants, all descendant blocks are copied and pasted with the ancestor block.