The disc, picture and sound terms you'll see on Blu-ray and 4K UHD listings, in plain English. Why physical media looks and sounds better →
The highest-resolution disc format: four times the detail of Blu-ray.
4K Ultra HD Blu-ray discs carry video at 3840 × 2160 pixels — four times as many as a regular Blu-ray — plus wider colour and, almost always, HDR. They need a 4K UHD player (a regular Blu-ray player can't read them) and look their best on a 4K TV. Many 4K releases include a regular Blu-ray disc in the box too.
If you have a 4K TV, this is the sharpest, most colourful way to watch a film at home — noticeably better than streaming, which is heavily compressed.
The shape of the picture: its width compared with its height.
Written as width:height, e.g. 1.78:1 (the same shape as a modern TV, also written 16:9), 1.85:1 (common for comedies and dramas) or 2.39:1 (ultra-wide 'scope' used for epics and action films). Older films are often 1.33:1 (4:3) or 1.37:1. A disc that preserves the original aspect ratio shows the film exactly as it was framed by the filmmakers.
It tells you whether to expect black bars. Wider films (2.39:1) show bars above and below on a 16:9 TV — that's correct, not a defect. Some IMAX releases switch between ratios for extra picture in key scenes.
An immersive surround format that adds a layer of height speakers.
Auro-3D is a 3D audio format that adds a height layer above a traditional 5.1 or 7.1 speaker setup. It appears on a small number of discs and needs a receiver that supports it; other receivers play the underlying surround track instead.
Rare, but if your receiver supports it you get overhead sound similar to Dolby Atmos.
High-definition disc format with 1080p picture and lossless audio.
Blu-ray discs hold 1920 × 1080 (Full HD) video and usually lossless surround sound such as DTS-HD Master Audio or Dolby TrueHD. They play in any Blu-ray or 4K UHD player and most game consoles. Blu-ray is the most common format for new releases and catalogue titles alike.
A big step up from DVD and streaming in picture and sound, at a lower price than 4K — and it works in far more players.
A code in the box that unlocks a streaming version of the film.
Many discs include a code (usually on a paper insert) that you redeem on a service like Movies Anywhere to add the film to your digital library. Codes can expire and are normally one-time use, so a used copy may not include a working one.
A handy bonus for watching on phones, tablets or while travelling — but don't count on it when buying second-hand.
How many physical discs come in the case.
Combo packs often contain one disc per format — for example a 4K UHD disc plus a Blu-ray — while special and collector's editions may add bonus-feature discs. Box sets can contain dozens. Digital codes are not counted as discs.
It tells you what's actually in the box: a 4K + Blu-ray combo lets you play the film on a player without 4K support, and extra discs usually mean more bonus features.
Object-based surround sound that adds height — sound from above you.
Instead of assigning sounds to fixed channels, Dolby Atmos places up to 128 sound 'objects' in 3D space, including overhead. With ceiling or upward-firing speakers (or an Atmos soundbar) rain, aircraft and ambience come from above. On discs, Atmos is carried inside a Dolby TrueHD track, so systems without Atmos still play lossless 7.1 surround.
It's the most immersive home audio format available. Even without height speakers you still get the lossless TrueHD track underneath.
The older, compressed 5.1 surround format found on DVDs.
Dolby Digital (AC-3) is a lossy surround format — typically 5.1 channels — used on DVDs, TV broadcasts and streaming. It's widely compatible but compressed, so it lacks some of the detail of lossless tracks like Dolby TrueHD or DTS-HD Master Audio.
If a Blu-ray only lists Dolby Digital for the main film, its sound will be closer to DVD quality than it could be.
Lossless surround sound — identical to the studio master.
Dolby TrueHD is a lossless audio format supporting up to 7.1 channels, meaning the sound is bit-for-bit identical to the studio master with nothing thrown away by compression. It's also the container that carries Dolby Atmos on discs.
Lossless audio has more detail, clearer dialogue and punchier bass than the compressed audio used by streaming services.
Advanced HDR that adjusts brightness and colour scene by scene.
Dolby Vision is a premium HDR format that uses dynamic metadata: brightness and colour instructions that change scene by scene (or even frame by frame), so your TV can show each shot as intended. It supports up to 12-bit colour. You need a Dolby Vision TV and player; otherwise the disc falls back to its HDR10 layer.
On a compatible TV it usually gives the most accurate, detailed highlights and shadows — especially on TVs that aren't very bright.
Lossless surround sound — DTS's equivalent of Dolby TrueHD.
DTS-HD Master Audio (DTS-HD MA) is a lossless format supporting up to 7.1 channels. It's the most common lossless track on Blu-ray, and receivers without DTS-HD MA support still play a compatible core DTS track.
Studio-quality sound with no compression loss — richer and clearer than streaming audio.
Object-based 3D surround sound — DTS's rival to Dolby Atmos.
DTS:X is an immersive, object-based audio format that places sounds anywhere around and above you. It's flexible about speaker layouts, and its core is a DTS-HD Master Audio track, so non-DTS:X systems still get lossless surround.
Like Atmos, it adds height and precise placement for a more immersive mix — and still sounds great on a regular surround setup.
Standard-definition disc format (480p) — the most widely compatible.
DVDs hold standard-definition video (720 × 480 in North America) with compressed Dolby Digital or DTS audio. They play in almost any disc player, including Blu-ray and 4K players, but look soft on modern large TVs.
Cheapest and most compatible, but a noticeable step down in picture and sound from Blu-ray.
Brighter highlights, deeper shadows and richer colour than standard video.
High Dynamic Range expands the range between the darkest and brightest parts of the picture and allows a much wider range of colours than standard dynamic range (SDR). Sunlight, explosions and neon glow look bright and vivid while dark scenes keep their detail. HDR10, HDR10+ and Dolby Vision are the formats you'll see on 4K discs.
Many viewers find HDR a bigger visible upgrade than the jump in resolution from 1080p to 4K.
The standard HDR format every 4K UHD disc and HDR TV supports.
HDR10 is the baseline HDR format: 10-bit colour with static metadata, meaning one set of brightness instructions for the whole film. Every 4K Ultra HD Blu-ray with HDR includes it, and every HDR TV can play it.
It guarantees HDR on any HDR TV. Dolby Vision or HDR10+ can improve on it when your TV supports them.
HDR10 upgraded with scene-by-scene brightness adjustments.
HDR10+ adds dynamic metadata to HDR10, letting the picture adjust brightness and tone mapping scene by scene — similar to Dolby Vision. It's royalty-free and supported mainly by Samsung, Panasonic and some other TVs. Discs with HDR10+ still play in HDR10 on TVs that don't support it.
On a compatible TV, highlights and dark scenes are handled more precisely than with plain HDR10.
The spoken-language audio tracks included on the disc.
Discs often include the original-language soundtrack plus dubbed tracks in other languages. The main track usually has the best audio quality (e.g. Dolby Atmos), while dubbed tracks may be in a simpler format such as Dolby Digital 5.1.
Check this for foreign-language films (to be sure the original audio is included) or if you want a dub for family viewing.
Uncompressed digital audio — as pure as it gets.
Linear PCM is completely uncompressed audio, often used for mono or stereo soundtracks of classic films and for concert releases. It's lossless like TrueHD and DTS-HD MA, just without compression, so it takes more disc space.
Guarantees perfect audio quality, and every player and receiver supports it.
The film's age rating in the US: G, PG, PG-13, R or NC-17.
Ratings from the Motion Picture Association: G (general audiences), PG (parental guidance suggested), PG-13 (some material may be inappropriate for under-13s), R (restricted — under-17s need a parent or guardian) and NC-17 (adults only). 'Not Rated' or 'Unrated' usually means an extended or alternate cut that wasn't submitted for rating.
A quick guide to whether a film suits younger viewers — and 'Unrated' editions often contain extra footage.
How long the main feature lasts.
The length of the film itself, in minutes, not counting bonus features. Extended, director's or unrated cuts may run longer than the theatrical version, and some releases include more than one cut.
Useful for planning a movie night — and a longer runtime than you remember can mean an extended cut.
Traditional video without HDR — how regular Blu-rays and DVDs look.
Standard Dynamic Range is the conventional range of brightness and colour used by DVDs, regular Blu-rays and older TVs. It looks perfectly good, but can't reach the bright highlights or wide colour of HDR.
If a 4K disc lists no HDR, or you're buying a regular Blu-ray, expect SDR.
The company that released the disc.
The studio or label that produced and distributed this home-video release — a major studio such as Warner Bros., Universal or Disney, or a boutique label like The Criterion Collection, Arrow Video or Kino Lorber. Boutique labels often license films from the majors and give them new restorations and extras.
Boutique labels are known for careful restorations, rich bonus features and collectible packaging — often worth seeking out.
On-screen text tracks for dialogue, in one or more languages.
Discs include selectable subtitle tracks — often English, English SDH (Subtitles for the Deaf and Hard of hearing, which also describe sounds and music), Spanish and French. Foreign-language films need English subtitles to be watchable for English speakers.
Essential for foreign-language films and viewers who are deaf or hard of hearing — and handy for mumbled dialogue.
Audio spread across multiple speakers around the room.
The numbers count the speakers: 5.1 means five main speakers (front left, centre, front right, two surrounds) plus one subwoofer (the '.1'); 7.1 adds two rear speakers. Atmos and DTS:X layouts add a third number for height speakers, e.g. 7.1.4.
It tells you how many speakers the soundtrack is mixed for — matching your setup gets you the full effect.