Microsoft provides another database product—the industrial-strength SQL Server, which powers everything from Microsoft’s own search engine to the NASDAQ stock exchange. Clearly, SQL Server is big business, and many Access fans wonder how their favorite database software compares. One of the most important differences between Access and database products like SQL Server is that Access is a client-side database. In non-techie terms, that means that Access runs right on your personal computer. Database engines like SQL Server are server-based: They store the data on a high-powered server computer, which you access from a garden variety PC. (This interaction happens over a local network.)
Server-based databases are much more complex to set up and maintain, but they provide enhanced performance and rock-solid stability, even when thousands of people use them at once. However, the only people that require high-end databases like SQL Server are large organizations. Amazon.com wouldn’t last 5 minutes if it had to rely on an Access database. But Access works just fine for most small and mid-sized businesses. It’s also perfect for personal use.
Another important difference between Access and server-side database products is that Access is an all-in-one solution for storing and interacting with data. Serverside database engines like SQL Server focus exclusively on storing data (and sending that data to other computers when they request it). However, this single-minded design has a sizable price. An ordinary person can’t directly edit a database that’s stored by SQL Server. Instead, you need to use yet another program that can talk to SQL Server and ask for the information it needs. In most cases, this program needs to be hand-built by a savvy programmer. In other words, if you’re using SQL Server, you need to write a whole application before you can effectively use your database.
Sometimes, Access fans do turn into SQL Server gurus. You can start with a modest Access database and then step up to SQL Server when your needs exceed what Access provides. The process isn’t always seamless, but it’s possible. You can even keep using Access as a front end to manage your SQL Server database.
Source of Information : Oreilly Access 2010 The Missing Manual