What is the purpose of file extensions?

File extensions serve a crucial role in computing by informing the operating system about the format of a file and indicating which program or application should be used to open it. Each extension is typically comprised of a period followed by a few letters, such as ".txt" for text files or ".jpg" for image files. When a file is accessed, the operating system recognizes the extension and determines how to process the file correctly. This functionality ensures that files are handled efficiently; for example, a word processor understands to open a ".doc" file for editing, while an image viewer would open a ".png" file for display.

Understanding the purpose of file extensions is fundamental for managing files effectively and troubleshooting any file-related issues, as the operating system relies on this information to execute the appropriate software for various file types.