What are the three characteristics of a LAN (Local Area Network)?

Small geographic area, single administrative authority, and high-speed bandwidth.

* A LAN's three defining traits: small area, one administrator, and high-speed local links. *

1. Small geographic area: Spans a home, school, office building, or campus
2. Single administration: Usually administered by a single organization or individual
3. High speed bandwidth: Provides high-speed connections to end and intermediary devices

Go deeper:

• Local area network (Wikipedia) — confirms the defining LAN traits: limited area, locally managed (single administration), and high Mbit/Gbit speeds.