Creator media glossary
The terms that come up constantly once you start converting, compressing or cropping video for a specific platform - defined plainly, with a link to the tool or spec page each one actually affects.
Aspect ratio
The proportional relationship between a video or image's width and height, written as two numbers like 9:16 or 16:9.
Resolution
The pixel dimensions of a video or image - width × height - which determines how much detail it can show.
Frame rate (FPS)
How many individual images ("frames") a video shows per second, measured in FPS. 24, 30 and 60 are the common values.
Bitrate
How much data a video or audio file uses per second of playback, usually measured in Mbps (video) or kbps (audio).
Codec
The algorithm that compresses video or audio data - H.264 and AAC are the two you'll run into most, packed inside a container like MP4.
Container format
A file format like MP4, MOV or WebM that wraps a video stream, an audio stream and metadata together - it's the packaging, not the compression.
H.264 (AVC)
The most widely supported video codec, decoded natively by essentially every phone, browser and TV made in the last fifteen years.
H.265 (HEVC)
A newer codec that roughly halves file size versus H.264 at similar quality, at the cost of narrower playback support.
AV1
A royalty-free codec built for streaming efficiency, offering meaningfully smaller files than H.264 or even VP9 at the same quality.
VP9
Google's open, royalty-free codec, typically paired with the WebM container, delivering H.264-level quality at roughly 30–50% less data.
MP4
The most widely compatible video container, accepted by every social platform, phone and editor.
MOV
Apple's QuickTime container - the default export from iPhone camera rolls and Final Cut Pro.
WebM
An open, web-native video container - typically VP9 or AV1 video with Opus audio - built for smaller files on the open web.
PNG
A lossless image format that preserves transparency - the standard choice for logos, screenshots and graphics with text.
JPEG
The standard compressed photo format - small files, no transparency, accepted everywhere.
WebP
An image format supporting lossy and lossless compression plus transparency; the quality and file size depend on the selected mode and source image.
Lossless vs. lossy compression
Lossless compression shrinks a file without discarding any data; lossy compression discards data a viewer is unlikely to notice, for a much smaller file.
Alpha channel
The transparency information stored in an image or video, alongside its red, green and blue color data.
Keyframe
A fully-encoded frame in a compressed video, placed periodically so playback and editing can jump to that point without decoding everything before it.
Transcoding
Converting a video or audio file from one codec, container or bitrate to another - decompressing it, then compressing it again in the new format.
Safe zone
The area of a video kept clear of interface overlays, where important text, faces and graphics are less likely to be obscured.
Caption limit
The maximum number of characters a platform allows in a post's caption - it varies enormously, from 280 on X to over 60,000 on Facebook.