MQL4 Data Types

Overview

MQL4 programs process data of various types. Data types influence processing speed and internal representation.

Basic Data Types

**Integers:** char, short, int, long, uchar, ushort, uint, ulong.

* Processed fastest.

**Logical:** bool.

**Literals:** ushort (for symbol constants).

**Strings:** string.

* Slowest processing due to dynamic memory allocation/reallocation.

**Floating-point numbers:** double, float.

* Processed using a co-processor, slower than integers due to internal representation complexity.

**Color:** color.

* Represented as an integer. * Used for visualization and input parameters.

**Date and Time:** datetime.

* Represented as an integer. * Used for visualization and input parameters.

**Enumerations:** enum.

Complex Data Types

**Structures:** Defined using struct.

**Classes:** Defined using class.

**Interfaces:** Defined using interface.

Type Characteristics

**Arithmetic Types:** Integer and floating-point types.

**Abstract Data Types:** Complex data types in the context of OOP.

**Typecasting:** Implicit type casting is used in expressions unless explicit casting is specified. See [Typecasting](/basis/types/casting).

Processing Speed

1. Integers (fastest) 2. Floating-point numbers (using co-processor, slower than integers) 3. Strings (slowest due to memory management)