FileGizmo Learn
Plain answers to file questions
Short, honest definitions of the terms behind everyday file work. Every entry ends with a private tool that runs in your browser, so you can act on what you just learned without uploading anything.
Image
CMYK vs RGB The difference between the color model screens use and the one printers use, and why colors shift. HEIC Apple's modern photo format that saves space but does not open everywhere. Lossy vs lossless The difference between compression that discards detail to save space and compression that keeps every pixel. OKLCH A colour format whose lightness matches what the eye actually sees, unlike HSL. WebP A modern image format that makes photos and graphics smaller than JPG or PNG at similar quality.
Data
Base64 A way to represent binary data, like an image, using only plain text characters. Colspan and rowspan Attributes that let one table cell cover several columns or several rows. HTML entity A way of writing a character that would otherwise change what the surrounding markup means. Number base How many distinct digits a numbering system uses before it carries into the next column. Transpose Swapping the rows and columns of a table, so the first row becomes the first column.
Security and privacy
EXIF data The hidden metadata your camera writes into a photo, including GPS location, device, and timestamp. JWT A compact, signed token that carries claims between a server and an app, used for login and authorization. Metadata The hidden data inside a file that describes it, like author, dates, location, and software used.