Build a Duplicate File Finder with Python and Hash Tables

Is your storage cluttered with identical files scattered across different directories? Building an automated tool to identify and clean these duplicates is a classic software engineering challenge that combines file system operations with efficient data structures. In this text-only course, you will learn how to design and write a robust duplicate file finder from scratch using Python. You will start with the foundational concepts of file systems, hashing algorithms, and hash tables (dictionaries), before moving on to practical implementation. By the end of this course, you will have a clear, step-by-step understanding of how to scan directories, handle large files memory-efficiently, and group duplicates accurately. What you'll learn: Understand the core concepts of file systems, paths, and metadata; Apply modern Python libraries like pathlib to traverse directories safely; Implement cryptographic hashing to generate unique fingerprints for file contents; Use Python dictionaries as hash tables to group files with identical content; Optimize memory usage by reading and hashing files in chunks; Practice writing clean, readable Python code with modern type hints. The course begins with essential terminology and the theory behind file hashing and hash tables. From there, you will read through structured explanations and code snippets to build the file-scanning logic, optimize it for large files, and handle edge cases like empty files. This course is designed for beginner to intermediate Python programmers who want to apply their coding skills to a real-world system utility. No advanced systems programming experience is required. Start reading today to master file-system automation and hash-based data structures in Python.