The owner of this site started his carieer in the currency department of the Central Bank of Norway. Later he moved to the research department and worked there for nearly 20 years. There is a large litterature on currencies and exchange rates. Purchasing power parity, Dornbursh's over shooting, mean reversion, random walk with or without drift, fractal structure and alike, we know most of them.
Note: Forex trading involves substantial risk of loss and is not suitable for all investors and traders.
The currency exchange markets are the markets of the giants. You have to understand the game if you want to trade or invest in the currency exchange markets. If you search the web for currency or forex trading or investment, you will get a lot of hits. You need to be sceptical to what you find.