Matplotlib
Matplotlib is a comprehensive Python library for creating static, animated, and interactive visualizations. It provides a MATLAB-like interface for plotting data in various formats, including line plots, scatter plots, bar charts, histograms, and 3D plots. It is widely used in data analysis, scientific computing, and machine learning for generating publication-quality figures.
Developers should learn Matplotlib when working with data visualization in Python, especially for scientific, engineering, or analytical applications where custom, high-quality plots are needed. It is essential for tasks like exploratory data analysis, reporting results in research papers, or creating dashboards, as it offers fine-grained control over plot aesthetics and integrates well with other data science libraries like NumPy and pandas.