How do you represent floating-point numbers in the C programming language?

In the C programming language, floating-point numbers are typically represented using two data types: float and double.

1. float: Declare a single precision floating point variable using the float keyword. It typically can represent 6 to 7 significant digits and occupies 4 bytes of storage space. For example: float num = 3.14f;
2. double: Declare a double-precision floating point variable using the double keyword. It can typically store 15 to 16 significant digits and occupies 8 bytes of storage space. For example: double num = 3.14;

When representing floating-point numbers, scientific notation can be used to represent larger or smaller numbers. For example, 1.23E-4 represents 0.000123, and 1.23E+6 represents 1230000.

It is important to note that due to the way floating-point numbers are stored in a computer as binary, precision loss may occur during floating-point arithmetic. When comparing two floating-point numbers for equality, it is advisable to use a margin of error for comparison rather than directly using the equal sign.