'Integrated Systems' is a broad term to describe a multi-faceted system in which everything communicates and works together.
Commercial systems can be quite similar but include things such as card entry and logging, fingerprint access, automated locks, cameras, paging systems, etc.
There are many benefits of having an integrated system vs. many independant systems. The biggest advantage being ease of use and the ability to accomplish several things with a single push of a button.
Another perk is the ability to see feedback in real time, like knowing if certain lights are on or off and seeing current and requested temperatures. Also there is the ability to have alarms or email alerts if something goes awry.