A table is just what it sounds like, a table of information. These are used when you have static information that may need to get pulled into your documents over and over again – for example, you could have a table with all of the different states listed. Tables allow you to tie different information to one entry, which can be useful when you want several items to be related to a single answer.
Example: For the 'New York' state entry in your table, the first and main entry would be New York. Then you might have a column for the postal abbreviation (NY) and a column to reference the state's department of labor (New York State Department of Labor). This way, when you have a state tied to a particular piece of information – like an individual or an entity – you can use that one answer to pull information from the relevant column into your documents, instead of having to enter it separately.
Here is a video that shows how tables work.