Reference
File Format Guides
Plain-English guides to the file formats you work with every day: what each one is for, where it falls short, and the free browser tools that read and write it.
data formats
.jsonJSON A lightweight, text-based format for structured data built from objects, arrays and primitives..xmlXML A tag-based markup format for structured documents and data with attributes, namespaces and schemas..csvCSV A flat, row-and-column text format where each line is a record and fields are separated by a delimiter..yamlYAML An indentation-based data format designed to be comfortable for humans to read and edit.
image formats
.pngPNG A lossless raster image format with full alpha transparency..jpgJPG A lossy raster format tuned for photographs, with adjustable quality..webpWebP A modern image format offering both lossy and lossless modes plus transparency..svgSVG An XML-based vector format that scales to any size without losing sharpness.
document formats
.mdMarkdown A plain-text writing format that converts predictably to HTML..pdfPDF A fixed-layout document format that renders identically on every device..docxDOCX The Microsoft Word document format — a zipped bundle of XML parts..xlsxXLSX The Excel workbook format, with multiple sheets, formulas and formatting..zipZIP A compressed archive that bundles a folder tree into one file.
encoding formats
.txtBase64 An encoding that represents binary data using 64 printable ASCII characters..txtJWT A signed, Base64URL-encoded token carrying JSON claims..txtUUID A 128-bit identifier that can be generated independently without collisions..txtURL The escaping rules that let arbitrary text travel safely inside a URL.
code formats
.sqlSQL The declarative query language used to read and modify relational databases..txtCron A five- or six-field syntax describing when a recurring job should run..txtRegex A pattern language for matching, extracting and replacing text..tsTypeScript Typed JavaScript — interfaces and types that describe the shape of runtime data.