Chart patterns like triangles, or the famous head and shoulders formation are often referenced in the technical analysis of forex trading. For example, a reversal chart pattern like the double top can indicate that the top has been reached and a southward turn in the price is more likely than further gains.
Are forex patterns legit?
Well, this depends on the trader you ask. Most say that patterns along forex indicators are not something you should rely on exclusively, but rather an additional piece in the puzzle that might be relevant in some cases.
The best is to always gather as much information as possible. This also includes fundamentals, like macro data about the economies represented by the currency pair in question.