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The term “codec” comes up a lot when discussing audio and video formats, as well as compression techniques used to make files smaller. But what exactly is a codec, and where does the term come from?

Codecs Are Used to Store and Stream Data

The word codec comes from the terms “coder” and “decoder” which roughly describes a codec’s job in terms of data transmission and storage. While modern codecs are software-based, in the past hardware codecs were more common particularly when analog formats first started to be digitized.

“Codec” is a term used to describe software that can encode and decode data. As an example, an MP3 codec is used to create MP3 files from audio data. To play that MP3 file back on a computer or separate device, you’ll need a codec that can decode the format.

In essence, a codec is used to encode data in a format that can be transmitted or stored and later viewed with a counterpart decoder.

While the term codec is a portmanteau of the words coder and decoder, the same software isn’t necessarily always able to perform both tasks. Some encoders are premium software, with some notable examples being the original LAME MP3 encoder and DivX video encoder.

In the world of video, H.264 (AVC) and H.265 (HEVC) are two of the most common codecs used across the web. While H.264 was designed with software decoding in mind, the H.265 codec relies on devices that support hardware acceleration to decode the video signal allowing for better quality and lower space or bandwidth requirements.

Codecs Are Essential for Media Compression

The common thread among all of the codecs mentioned in this article so far is that they are used for one purpose: compressing data. Data compression is used in everything from sharing video and audio over the internet to carrying a wireless audio signal from a smartphone to a pair of Bluetooth headphones.

When data is encoded in a particular format to save space, a counterpart decoder is required to display that data on the other end. Some codecs like the MP3 format are lossy, which means that some data is discarded in the compression format. Others, like FLAC, are lossless which means that no loss in quality can be discerned once the data is decompressed again on the other side.

Codecs are also used for encryption purposes, as a means of making data accessible only to devices that possess the correct decoder.

RELATED: What Is Lossless Audio?

Codecs Aren’t the Pain They Used to Be

Back in the day, you’d probably catch yourself installing codec packs to play certain types of video or audio downloaded from the web. As time goes on, more and more devices can do it all.

Modern computers, smartphones, and televisions are all equipped with hardware decoders that can handle formats like H.265 with little bother. If you are having trouble getting a video to playback on an older device, try converting the video to H.264 with a free video converter.

Profile Photo for Tim Brookes Tim Brookes
Tim Brookes is a technology writer with more than a decade of experience. He has covered a wide range of topics including Apple, security, productivity tips, gaming and more for publications like How-To Geek, Zapier, and MakeUseOf.
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