A bar chart shows a picture of what is happening in the market.
A technical analyst uses these three important sources of market information in the process of predicting prices:

Open interest (the number of outstanding contracts – that is, the number that have not been offset)

An analyst creates a picture of what is happening in the market by recording this information on a bar chart. It is important to realize that the analyst is recording history, or what has already happened. The bar chart does not show what is going to happen. The analyst is educated to read the visual patterns of price movement and is able to draw conclusions about the likely future direction of the market.

A bar chart of price movement is made for a specific futures contract for a specific commodity. The vertical axis represents the price of the commodity; the horizontal axis represents time, but trading days only. The high, low, and closing prices are recorded each day. A vertical line is drawn to show the range of prices for the day. A sideways tic shows where the market closed. The example here shows how to record hog prices. On the first of the month, prices ranged from $63.50 to $65.50 per cwt. and closed at $64.00. On the second, prices ranged from $64.00 to $67.50 and closed at $65.50.








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