A histogram is a graphical representation of the distribution of numerical data. It consists of bars that represent the frequency of data points within specified ranges, known as bins. The height of each bar indicates how many data points fall within that range, allowing for a visual interpretation of the data's distribution, central tendency, and variability. Histogram techniques involve selecting appropriate bin sizes and ranges to accurately reflect the data's characteristics. Common methods include the Sturges' rule, which suggests a formula for determining the number of bins based on the data size, and the Freedman-Diaconis rule, which considers data variability for better bin width selection.