Every video you have ever played on your devices comes in a specific format. These are usually different on computers, smartphones, tablets and TVs, and each video file format has certain strengths and weaknesses that make the difference. In case this is your first contact with the notion of formats, you should start by getting to know the most common ones. To find out the format of a given file on Mac, right-click it and click "Get Info", then under "More Info" you should see its video and audio codecs.
Any video file consists of a container and the tracks within. The container holds data about the tracks, and sometimes other information (overall, this is called "metadata"). The tracks themselves constitute pure audio, video and subtitle data. These tracks are compressed through the use of algorithms called “codecs”, and the same codecs are required to decrypt and play them on your Mac.
Short for Audio Video Interleaved, AVI is commonly used to store movies and TV shows. Most media players can open this format, even across different platforms. AVI offers decent compression without significant losses in quality. It can sometimes be found in use with promotional materials, trailers, short films and advertisements, since corporate clients prefer to use proprietary formats.
Another format you might encounter is MKV, a collaborative effort by the Matroska Project. Much like AVI, it supports a variety of codecs, allowing for compression and efficient storage. The main difference lies in metadata: MKV is more flexible in this regard. Also, because it’s an open format, tools to create, edit and read MKV metadata are freely available.
Play MKV files with an MKV Player for Mac
A relic of a long forgotten format war. WMV was created by Microsoft to compete with other streaming file types, which included AVI and MOV. After having been standardized by SMPTE, WMV was released to the public. It found some use at the time, but nowadays, there are better choices, especially since .wmv isn’t actively supported on macOS.
MP4 has become commonplace nowadays - not without a reason. Earlier, many hardware vendors chose to provide native support for the format, allowing phones and tablets to decode the videos quicker. Since then, it has become a de-facto standard for portable devices and online streaming. Initially, MP4 was based on a proprietary Apple format, and now, in turn, Apple has adopted MP4 and its derivative formats.
Here’s a format you don’t see every day. VOB files are found on DVD discs, and they contain everything - from menus and tracklists to videos themselves. If you’re looking to back up some of your old DVDs, you might run into issues - the disc may be encrypted, keeping that sweet, sweet .vob out of your reach.
You already know enough about the best video formats. If you’re also looking for the best media player for Mac, read our review.
MP3 is a highly popular lossy audio format. It offers reasonable quality, combined with extremely low file sizes. This doesn’t come without a cost: after compression, some audio data is lost permanently. At lower compression levels, the difference is inaudible, so most people choose to have smaller files, rather than perfect sound. And the benefits are pretty clear: at the same level of quality, a soundbite that takes up 30 MB in .wav format would only take up 3 MB as an MP3 file.
To use MP3 to the fullest, read up on our Top Mac music players.