Data analysis is the process of evaluating data using statistical and computational techniques to uncover patterns, trends, and relationships. It involves cleaning and preparing data, exploring and visualizing data to discover insights, and using statistical and machine-learning techniques to make predictions or inform decision-making.

There are many tools and techniques used in data analysis, including Excel, SQL, R, Python, and others. The specific tools and techniques used depend on the nature of the data, the questions being asked, and the goals of the analysis.

Data analysis is an important skill in many fields, including business, finance, science, and public policy. It is used to inform decision-making, develop new products and services, and understand complex phenomena. Data analysts, data scientists, and other professionals who work with data use data analysis to extract meaning from data and communicate their findings to others.