This is about identifiers in a record referring to other records.
You can have many to one, one to one, many to many.
E.g., if you have two tables, Authors and Books, then a book record could have a reference to an author record. Since an author can write many books, this would be a many-to-one relationship.
Simplex, simplex, and half duplex.
Hope this helps!!
the reason HTML seems to work even if it has syntax errors is due to browser having built in ways to parse the code meaning it will still show but most likely look way different then you would want.
the code may turn pink due to syntax errors
