MQL4 (MetaQuotes Language 4) and MQL5 (MetaQuotes Language 5) are integrated programming languages designed for developing trading robots, technical market indicators, scripts and function libraries within the MetaTrader software.
The primary objective of MQL4 and MQL5 is automation of trading and facilitation of operational analysis. MQL4 and MQL5 comprises an extensive codebase source code library used for developing trading robots.
Video MetaQuotes Language MQL4/MQL5
History
On July 1, 2005 MetaQuotes Software released MetaTrader 4 - a platform for trading on financial markets. MQL4 - an object-oriented programming language, was written specifically for work on this platform. Initially, its syntax was based on C. Another platform, MetaTrader 5, was released in 2010 together with MQL5 - a new language created for it.
The release of MetaTrader 4 600 build in 2014 was a major update of the language. That brought it to the level of the more modern MQL5. The development environment MetaEditor became unified for both languages.
The updated MQL4 features new graphical objects and new functions borrowed from MQL5 and used for analyzing charts. The protection system was completely modified for the executable files EX4. The MQL5 Standard library was transferred almost entirely with the only exception of the trade subsystem, which required adaptation. New data types were added and the micro substitution system expanded (conditional compiling #ifdef, #ifndef, #else,