Charts are graphical representations of the price movements and trading activity of a particular option or options contract. They can be used to analyze and predict future price movements, as well as to identify trends and patterns in the market.

There are many different types of option trading charts, including line charts, bar charts, and candlestick charts. Line charts are the most basic type of chart, and they simply plot the closing price of an option over a specific time period. Bar charts are similar to line charts, but they also show the high and low prices for the option during the time period being plotted. Candlestick charts are a more advanced type of chart that show the opening, closing, high, and low prices for an option in a graphical format.

Option trading charts can be accessed through a number of online resources, including financial websites, trading platforms, and charting software. Some popular resources for accessing option trading charts include Yahoo Finance, Google Finance, and TradeStation. It's important to note that option trading charts should be used in conjunction with other tools and analysis techniques, as they are just one piece of the puzzle when it comes to making informed trading decisions.

There are several chart patterns that can indicate a potential reversal in the trend of a stock or other security. Some common reversal patterns include:

1. Head and shoulders: A head and shoulders pattern is a chart formation that consists of a peak (the left shoulder), a higher peak (the head), and a second lower peak (the right shoulder). This pattern is considered to be a bearish reversal signal, as it suggests that the asset's price may be about to decline.

2. Double top: A double top pattern is a chart formation that consists of two peaks at approximately the same price level. This pattern is considered to be a bearish reversal signal, as it suggests that the asset's price may be about to decline.

3. Double bottom: A double bottom pattern is a chart formation that consists of two troughs at approximately the same price level. This pattern is considered to be a bullish reversal signal, as it suggests that the asset's price may be about to rise.

4. Rounding bottom: A rounding bottom pattern is a chart formation that consists of a series of troughs and peaks that form a U-shape. This pattern is considered to be a bullish reversal signal, as it suggests that the asset's price may be about to rise.

5. Cup and handle: A cup and handle pattern is a chart formation that consists of a "cup" with a downward sloping rim and a small "handle" with a downward slope. This pattern is considered to be a bullish continuation signal, as it suggests that the asset's price may continue to rise.

6. Wedges: A wedge pattern is a chart formation that consists of two converging trend lines that slope upwards or downwards. There are two types of wedges: rising wedges, which are considered to be bearish reversal patterns, and falling wedges, which are considered to be bullish reversal patterns.

7. Pennant or flags: A pennant or flag pattern is a chart formation that consists of a small consolidation period following a sharp price move. There are two types of pennants: bull pennants, which are considered to be bullish continuation patterns, and bear pennants, which are considered to be bearish continuation patterns.

8. Ascending triangle: An ascending triangle pattern is a chart formation that consists of a horizontal resistance level and an upward sloping trend line. This pattern is considered to be a bullish continuation signal, as it suggests that the asset's price may continue to rise.

9. Descending triangle: A descending triangle pattern is a chart formation that consists of a horizontal support level and a downward sloping trend line. This pattern is considered to be a bearish continuation signal, as it suggests that the asset's price may continue to decline.

10. Symmetrical triangle: A symmetrical triangle pattern is a chart formation that consists of two converging trend lines that slope upwards and downwards. This pattern is considered to be a neutral pattern, as it does not provide a clear indication of the asset's future price direction.

It's important to note that these patterns are not always reliable indicators of a trend reversal, and should be confirmed with other technical analysis tools and indicators, such as trend lines, moving averages, and volume. It's also important to consider fundamental analysis, such as the financial health and industry conditions of the company whose stock you are analyzing.