A quartile is a statistical term that divides a data set into four equal parts. Each quartile represents a specific range of values, helping to understand the distribution of the data. The first quartile (Q1) marks the 25th percentile, meaning 25% of the data falls below this value. The second quartile (Q2) is the median, dividing the data into two halves, while the third quartile (Q3) represents the 75th percentile, indicating that 75% of the data is below this point. Quartiles are useful in various fields, including finance, education, and healthcare, as they provide insights into data trends and variations. By analyzing quartiles, researchers can identify outliers and assess the spread of data, making it easier to compare different data sets. This statistical tool is essential for summarizing large amounts of information in a clear and concise manner.