Encountering the "ReferenceError: Buffer is not defined" error typically arises when using the Buffer class in a browser environment, as it is exclusive to Node.js, or when running an outdated Node.js version that doesn't support it. The Buffer class in Node.js is essential for handling binary data, which is useful for file operations, network packet management, and data encoding/decoding. To resolve this error, you should upgrade to a recent Node.js version if using an older one, ensure the script is executed in a Node.js environment rather than a browser, and utilize the Buffer.from() method instead of the Buffer constructor in newer Node.js versions. Additionally, managing, tracking, and analyzing such errors can be streamlined using tools like Rollbar, which offers automated error monitoring and triaging to ease the process of fixing Node.js errors.