Until recently, traders who lacked the time to learn MQL4 or had no background in computer programming were largely unable to easily create and use their own Expert Advisors. Creating and using your own Expert Forex trading expert advisors now only requires creating your own trading strategy. By downloading and running these Expert Advisors, you can see how easy it is to convert a mechanical trading style into a new forex robot.
Each of these Expert Advisors uses a different trading strategy to trade the market. These strategies are simple robots built around relatively unsophisticated trading criteria. EAs allow for an almost infinite degree of customization and specialization for every strategy. Feel free to experiment with these strategies and see how they work for you. MQL4, we work with traders further to help refine or distill their new Expert Advisor. In principal, every user can develop his own EAs which will trade based on the programmed trading strategy, even automatically depending on the set up. A great number of Expert Advisors – discussed and tested in various forums- are offered at no cost in the internet.
Often the “Open Source” concept still prevails which means the source code is disclosed and can be used and modified by the traders at their discretion. On the other side, commercial Expert Advisors are closed systems, the source code cannot be accessed by the trader. For these cases the buyer needs to rely on the seller’s information regarding the programmed trading system as long as any information is disclosed at all. Many Expert Advisor providers have moved to a stronger protection of their source code. Basically you should have understood the Expert Advisor’s input parameters and trading strategy before its use, regardless whether you use a purchased version or an EA freely available in the internet.