Access is a baby RDBMS or Relational Database Management System. It runs SQL, stores its data in tables, provides queries (select with projection, DML, even DDL) and has code integration in the sense that VBA (Visual Basic for Applications – embedded, crappy VB Scripting) functions you write can be used in a SQL query.
In all honesty, SQL Server has allowed this forever with UDFs but only recently with the CLR. This is a unique way that Access has lead SQL Server if you simply must write your functions in Visual Basic.
This is a legacy tip – SQL Server has better support for XML by far, though, without even needing an external language like ASP. And SQL Server is free – Access is not. This defies the conventional wisdom that SQL Server is more expensive than Access (true in web hosting, and true if you buy enterprise versions of SQL Server).