N-Tier Architecture

Know the Vocabulary

This lesson uses the terms below repeatedly. Read them once now and return here when a later section needs one.

• Layer: A horizontal slice of the code with one technical job, such as handling HTTP or talking to the database.
• Tier: A part of the system that runs on its own machines and talks to the other parts over the network. Which parts count as tiers is partly a convention, but a load balancer that only forwards requests between tiers is usually not counted as one.