Recently, I've been studying technical analysis of forex trading and found that the Fibonacci indicator is really used quite frequently by many traders. Its principle isn't that complicated, but when used well, it can indeed help determine support and resistance levels.

First, let's talk about where Fibonacci comes from. In the 13th century, an Italian mathematician named Leonardo Pisano, nicknamed Fibonacci, introduced a mathematical concept discovered by an Indian mathematician into the Western world. This ratio is found everywhere in nature, and later traders applied it to financial markets.

The core is a magical sequence of numbers: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144... Each number is the sum of the two preceding ones. It looks simple, but when you divide one number by the previous one, for example 1597 ÷ 987, the result is approximately 1.618. This is the famous golden ratio.

Conversely, 144 ÷ 233 is about 0.618, which is the reciprocal of 1.618. Also, 55 ÷ 89 is approximately 0.382. These three ratios—1.618, 0.618, 0.382—are the basis traders use to find potential reversal points in price.

In actual trading, Fibonacci retracement lines, also called golden ratio lines, are used to identify potential support and resistance levels of an asset's price. The main percentage levels are 23.6%, 38.2%, 50%, 61.8%, and 78.6%. For example, if gold prices rise from 1681 to 1807.93, you can draw retracement lines between these two points. The 61.8% retracement level would be around $1729.49, and 38.2% at $1759.44. When the price retraces to these Fibonacci levels, it’s very likely to bounce back or continue downward.

The trading logic is basically: in an uptrend, first identify the bottom A and the top B, then see if the price finds support at Fibonacci levels. If the price stalls at 61.8%, it could be a good entry point. The same applies to downtrends, just in the opposite direction.

There’s also a tool called Fibonacci extension, which is used to predict where the price might go up or down. Extension levels like 161.8%, 200%, and 261.8% can help set profit targets. If retracement lines help you find entry points, extensions help you decide when to exit.

Most traders don’t rely solely on Fibonacci indicators; they usually combine them with other technical analysis tools or trend patterns for confirmation. But understanding this principle gives you an additional reference for judging potential turning points in price. If you're interested, you can try practicing on your trading platform using Fibonacci tools on historical price movements.