Three kinds of help, in the order you are likely to need them: how to perceive at all, what happened across nine centuries, and what one particular period demands of you.
Period-agnostic. These teach the vocabulary and the attention; everything else on the site assumes them.
How to hear anything — texture, rhythm, timbre, line — before you know what period it is.
How to look at anything — line, light, surface, space — before you know who painted it.
One thread, six periods, in order. Use these when you want the arc rather than the technique.
Gold-ground to fragmentation — the full cross-period visual survey.
Plainchant monophony to Modernist atonality, with listening for every period.
Cathedral portals to Modernist abstraction — three threads across six periods.
Built for periods that break the ordinary rules badly enough to need their own instructions. Each one is also linked from the period page it belongs to.