Free · No signup
See the rules of the water.
Learn the essentials through clear, interactive visuals—from give-way rules, lights, and sound signals to buoyage, charts, sailing, radio, and anchoring.
Free · No signup · Official sources cited · Progress stays on this device
Explore by topic
Lights & Shapes
Every light configuration in rotatable 3D — day shapes included.
ExploreSound Signals
Hear every horn, bell, and gong signal — then identify them by ear.
ExploreRules of the Road
Who gives way, in plain language, with the official text beside it.
ExploreBuoyage
IALA marks that actually blink — Region A and B.
ExploreLight Characteristics
Decode any charted light — Fl(2)WRG.10s — and watch it live.
ExploreChart Symbols
The chart symbols recreational skippers need most.
ExploreSails & Wind
Points of sail and apparent wind, interactive.
ExploreMarine Radio
Know what belongs on Channel 16, Channel 70, and a working channel.
ExploreAnchoring
Choose the spot, calculate scope, set the anchor, and verify it holds.
ExplorePractice Quiz
Drill any topic with instant feedback and explanations that link back to the visuals.
ExploreMade to be recommended
Instructors can deep-link any light, rule, or buoy straight into course notes and slides. Every fact cites its rule and official source.
Built on official sources
Rule text comes from the public-domain USCG Navigation Rules; chart-symbol concepts follow IHO INT 1, with Imray's published key used for small-craft symbols. Educational redraws and questions are our own.
Accessible by design
Color-vision-friendly modes, keyboard-friendly 3D with named viewpoints, and sound quizzes that are fully answerable visually.