How is data type conversion performed from one type to another in programming?

Data type conversion from one type to another in programming is called type casting or type conversion.

In C#, there are two main ways:

1. Implicit conversion — when the compiler automatically converts the type, for example, from int to double.

2. Explicit conversion (casting) — when the programmer explicitly specifies the conversion, for example:

int i = 42;
double d = (double)i; // explicit conversion of int to double

There are also methods for conversion, such as Convert.ToInt32(), int.Parse(), which are used to convert strings to numbers and vice versa.

It is important to consider the possibility of data loss during conversion, for example, when converting from double to int, the fractional part is discarded.