What is "gd"

GD is an open source library for dynamic image creation by programmers. GD is written in C, and "Wrappers" are available for Perl, PHP and other languages. GD creates PNG, JPEG, GIF, Webp, XPM, BMP images, among other formats.

GD is commonly used to generate graphics, thumbnails and anything else at runtime. Although not restricted to web use, the most common GD applications involve website development.

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