The decisions to invest money to reap better rate of return is basically depends on some aspects called the economic analysis, the fundamental analysis and the technical analysis. These analyses actually represent a portrait of present and future of economic, fundamental and technical status of currencies where you want to invest your money.
The technical analysis is a task applied basically to determine the future possible prices for the currencies and future price possibilities are actually are calculated on the bases of past prices of the currencies. Beyond price information, the technical analysis use data about the volumes of currencies traded and data about open interest in future contracts.