A frequency table is a tabular representation that summarizes raw data by displaying the number of times each category or interval occurs. It is highly useful in descriptive statistics for organizing data into two primary types:

• Categorical (Qualitative) Tables: Used for non-numeric categories (e.g., color, names, types). Each row lists a unique category and its raw count.
• Grouped Numeric (Quantitative) Tables: Used for continuous or wide-ranging numeric data. The dataset is divided into contiguous, non-overlapping intervals called class intervals or bins to show density.

• Frequency ($f_i$): The raw number of observations in a particular category or interval.
• Relative Frequency: The proportion of the total observations that belong to a category, calculated as $f_i / N$.
• Cumulative Frequency: The running total of frequencies up to and including the current class interval.
• Sturges' Rule: A widely-used rule of thumb to estimate the optimal number of bins ($k$) for a numeric dataset of size $N$:
  $k = 1 + 3.322 log_{10}(N)$