SASS provides powerful functions that allow for advanced manipulation of values and the ability to create reusable code. Functions in SASS can be used to perform various operations, such as modifying colors, manipulating strings, and performing mathematical calculations.

One commonly used function in SASS is the lighten() function. It allows you to lighten a color by a specified percentage. For example, lighten($color, 20%) will make the color 20% lighter.

Another useful function is the rgba() function, which enables you to set an alpha value for a color. This is particularly helpful when creating transparent backgrounds or overlays. For instance, rgba($color, 0.5) will set the color's transparency to 50%.

In addition to functions, SASS also provides a range of operators that allow for mathematical calculations and manipulation of values. The basic arithmetic operators include +, -, *, and /, which can be used to perform addition, subtraction, multiplication, and division respectively.

By utilizing functions and operators in SASS, you can enhance your stylesheets with dynamic and flexible behavior.