The document contains 23 JavaScript code snippets showing how to: 1) Perform basic math operations like addition, subtraction, multiplication and division of two numbers. 2) Calculate the area and perimeter of basic shapes like circle, rectangle, triangle. 3) Check if a number is even or odd. 4) Find the largest of two numbers. 5) Print multiplication tables and sequences of numbers. 6) Calculate sum, factorial, square and length of a string. 7) Find difference between dates. 8) Reverse a string. The code snippets demonstrate JavaScript functions, loops, conditional statements, prompts and alerts.