In the world of data processing, CSV files are among the simplest and most ubiquitous file formats. Their straightforward structure—a grid of rows and columns represented in plain text—makes them suitable for transferring data across applications, especially in contexts where lightweight solutions are essential. But processing these files efficiently in Java requires a clear understanding of techniques, challenges, and tools available. In this article, we focus on the process of reading, writing, and handling CSV files in Java, exploring practical examples and diving deep into their mechanics.