Why volume belongs next to price

Volume is how much actually changed hands in that candle. Price says where it went; volume says how many people were involved.

The main use: confirming a break

A break through a level on almost no volume and a break with volume are different events.

• With volume — enough participants agreed to matter
• Without volume — a handful of orders pushed it and nobody followed

Most "it broke and came right back" cases are the second one.

Drying up is information too

Volume shrinking inside a range usually means the fight is over for now. That is often what comes right before a big move — not a reason to act, but a reason to pay attention.

The usual mistake

Reading volume on its own. A big volume candle is not bullish or bearish by itself. It only means something together with where price was and what the candle did.

This is for learning and is not investment advice.