# Data misconceptions

## Volume

The volume on a forex bar is usually a count of price updates, not an amount traded. Every series says which kind it holds: tick volume or traded volume. A strategy that treats tick volume as money changing hands is measuring the broker's feed.

> **Trap.** A volume filter built on tick volume is a filter on how busy the feed was.

## Bid, ask and mid

Bars are built from one price side. Broker-quoted markets use the bid by default, and exchange markets use the last traded price. A feed with a single price, such as the Deriv public feed, is marked as such. A bar built from the ask is a different bar.

## Time zones

Every time inside Forge is UTC. A chart on a broker terminal shows server time, and a file can carry any of several clocks. See [broker time and the trading day](https://oathra.dev/docs/concepts/broker-time-and-the-trading-day).

## Gaps

A missing minute is a missing row. Forge does not fill it, and a bar made with no real price in it can never be filled against. Across a weekend or a holiday a bar can continue its grid or reset it, and the series says which.

> **Trap.** A weekend gap is not a loss of data. It is a closed market, and the gap between Friday's close and Sunday's open is real.