What is a GIF?

Where the format came from

CompuServe introduced GIF in 1987 to solve a practical problem: how to compress color images small enough to send over dial-up connections. The initials stand for Graphics Interchange Format. The engineers at CompuServe built it around LZW compression, a dictionary-based algorithm that was already in use for text files, and adapted it to work on pixel data.

The color palette limit of 256 colors per frame came from a technical constraint of that era, not a deliberate design choice. At the time, most computer displays could only show 256 colors anyway. GIF 89a, the version still in use today, arrived in 1989 and added two features that turned out to matter more than anyone expected: transparency support and animation.

How the 256-color limit actually works

Each GIF frame carries its own color table, with up to 256 entries. Those 256 slots can be any 24-bit RGB colors — you are not limited to a fixed palette. You pick the best 256 colors for your image and map every pixel to the nearest one.

For photographs this creates obvious banding and dithering. Photos have millions of color variations, and trying to represent a sunset with 256 colors looks rough. But for flat graphics, cartoons, or text, 256 colors is often enough that you barely notice. Reaction GIFs shot on a phone camera tend to look washed out for exactly this reason.

One workaround: separate frames can each carry a different set of 256 colors. A long GIF with enough frames can represent more color variety across the whole clip, but each individual frame is still limited to its own 256-color table.

Why GIFs loop

Looping was added as a Netscape extension in 1995, not part of the original standard. Netscape added a metadata block that specifies how many times to repeat the animation, and browsers adopted it. A loop count of 0 means "repeat forever," which became the default most tools use.

The decision to loop forever was practical: it meant a small animated graphic could sit on a webpage and keep moving without any user interaction or JavaScript. That same behavior is why GIFs work in places where video does not — email clients, chat apps, old CMS platforms, Slack messages, and anywhere that strips embedded media but allows images.

Why GIF files can get large

A 10-second GIF at 24 frames per second contains 240 separate images. Each frame stores its full pixel grid. Even with LZW compression, that adds up fast. A 480x270-pixel GIF at 15fps for 5 seconds can weigh anywhere from 1 MB to 10 MB depending on how much motion is in the frame.

Modern video formats (H.264, VP9, AV1) are far more efficient because they store inter-frame differences rather than full frames. A video equivalent of a 5 MB GIF is often under 200 KB. GIPHY, Tenor, and most major GIF platforms actually serve MP4 or WebP animations to browsers that support them, while keeping the .gif URL for compatibility. What you think of as a GIF is often a video file in a trenchcoat.

How GIF differs from video

The biggest practical differences: GIFs embed in anything that accepts images, loop automatically without a play button, and require no codec support. They also degrade predictably. A browser with no video codec support can still display a GIF. An email client that strips video tags still renders a GIF.

Video has a lower file size for the same quality and can represent any color without palette limits. But video requires a player, a play button, and usually a click before it runs. In chat contexts especially, that friction matters. A GIF starts playing the moment it loads.

The pronunciation debate

Steve Wilhite, who created the format, said in a 2013 Webby Award speech that it is pronounced like the peanut butter brand: "jif." The internet has mostly refused to accept this. Both pronunciations are in common use. The Oxford English Dictionary lists both as valid. You can pick whichever you want and be technically correct, which is the best kind of correct.

So why does it still exist?

Inertia, mostly. The .gif extension has cultural meaning now. When someone says "send me a GIF," they mean a short, looping, shareable animation, regardless of whether the underlying file is actually a GIF. The format name has become a category.

From a technical standpoint, WebP animated images and APNG offer better compression and full color support. But neither has the same universal support across every chat client, CMS, and email client that GIF has accumulated over 35-plus years. GIF survives because it works everywhere, not because it is the best tool for the job.