Integration techniques are methods used to calculate the integral of a function, which is a fundamental concept in calculus. These techniques can be classified into various categories, including analytical methods like substitution and integration by parts, as well as numerical methods that approximate the integral when an exact solution is difficult to obtain. Numerical integration techniques, such as Trapezoidal Rule and Simpson's Rule, are particularly useful in applied mathematics and engineering. They allow for the estimation of areas under curves and are essential in solving real-world problems where functions cannot be integrated analytically.