Reading a price chart without fooling yourself

A market page gives you a handful of figures. Each answers a narrow question.

Price

The last traded price, usually against the dollar. It is a snapshot, and it is already old.

Change over a period

Movement over one hour, a day, a week. The window matters enormously: an asset can be up on the day and far down on the month.

Market capitalisation

Price multiplied by circulating supply. Useful for scale, misleading as a measure of money invested: you cannot sell the whole supply at the last price.

Volume

How much traded in the period. The most practical number for a swapper, because it tells you whether a pair is liquid enough to fill at a sensible rate.

What none of it tells you

Where the price goes next. Charts describe what happened. The useful question before a swap is whether the pair is liquid and the rate is fair today.