File formats store information structured for easy storage and processing. A file format standards data storage in files. File extensions indicate formats. They follow the period in filenames. File extensions tell programs the format to open files in. Manually changing extensions or removing them does not change formats. Just filenames. This causes problems opening files without right extensions.
Computers use many Windows formats. Webopedia lists thousands of extensions and formats. This helps track software file extensions. PDF files end in .pdf. Opening them depends on extensions. Changing to .txt won’t make PDFs text. It will break opening them correctly.
Extensions define opening programs and formats. Document extensions indicate text or information files. Contents depend on format. Could be text, images, audio, video or CSV values. Formats and extensions say which software opens. Windows and macOS allow manually changing them. This changes opening programs.
File extensions should match formats, like .png. Missing or wrong extensions cause unknown formats. Computers can’t open unknown formats well. So logical to know major formats, purposes and extensions. Identifies document standards. Useful in daily work.
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