Rga is a line-oriented search tool that extends the capabilities of ripgrep to search in various file types, including PDFs, E-Books, Office documents, zip, tar.gz, and more. It uses adapters to convert binary or unreadable text documents to plain text, allowing for accurate searching. Rga can be installed on Linux, macOS, and Windows, and has various options for customization and integration with other tools. The tool is designed to be fast and efficient, with caching and recursive searching capabilities.