What Is HLS? HTTP Live Streaming Explained

By Sampath Mallidi, CEO of Revidd · Last updated June 2026

HLS is the protocol behind most of the video you watch online, but it is rarely explained plainly. Here is what it is and why it matters for delivering streaming to every device.

HLS (HTTP Live Streaming) is a widely used streaming protocol, originally developed by Apple, that delivers video over standard web servers by breaking it into small segments and adapting quality to each viewer's connection. It is the dominant way video is delivered to phones, computers, smart TVs, and streaming devices, and it is what makes smooth playback across different connection speeds possible. Apple maintains the official HLS specification and developer tools, and the protocol is now supported natively across the major device platforms.

How Does HLS Work?

HLS works by splitting a video into small chunks (typically a few seconds each), encoding each chunk at multiple quality levels, and letting the viewer's player request the right quality moment to moment based on their connection. The player downloads segments in sequence and switches quality up or down smoothly as bandwidth changes.

This is called adaptive bitrate streaming. Because the segments are delivered over ordinary HTTP, the same infrastructure that serves web pages, HLS works through firewalls and on a standard content delivery network without special streaming servers.

A typical HLS stream has two kinds of file. The manifest (an .m3u8 playlist) lists the available quality levels and the order of segments. The segments themselves are the actual video chunks. The player reads the manifest first, then pulls segments as it needs them.

Why Is HLS the Standard for Streaming?

HLS became the standard because it delivers reliably across devices and networks using ordinary web infrastructure, and because adaptive bitrate keeps playback smooth when connections vary. A viewer on fast Wi-Fi gets high quality, a viewer on a weak mobile connection gets a lower quality that still plays without constant buffering, automatically.

For broadcasters, this matters because your audience watches on every kind of device and connection. HLS output is what connected TV platforms like Roku and Samsung expect to ingest, and it is what lets one stream reach an iPhone, a laptop, and a smart TV alike. A FAST channel, for instance, is delivered as an HLS stream; see our guide to launching a FAST channel.

What Is Adaptive Bitrate Streaming?

Adaptive bitrate (ABR) is the technique HLS uses to match video quality to each viewer's available bandwidth in real time. The same content is encoded at several resolutions and bitrates, and the player automatically picks the best one it can stream smoothly, switching as conditions change.

ABR is why modern streaming rarely buffers the way early online video did: instead of stalling, the stream simply steps down to a quality the connection can handle, then steps back up. A platform's video transcoding system produces these multiple quality levels from your source file before they ever reach a viewer.

HLS vs DASH: What Is the Difference?

HLS and MPEG-DASH are both adaptive bitrate protocols that split video into segments and switch quality based on bandwidth. The practical difference is reach: HLS is supported natively on Apple devices and across the broad device set broadcasters care about, while DASH is an open standard with strong support on Android and web but no native playback on Apple hardware.

For most broadcasters the answer is simple. HLS gives you the widest device coverage out of the box, including iPhone, iPad, Apple TV, Roku, and Samsung. Many platforms package both and serve whichever a given device prefers, but if you only output one, HLS is the safer default. You do not have to choose manually; the platform decides based on the requesting device.

What Does HLS Mean for Broadcasters?

It means your platform should output HLS with adaptive bitrate so your content plays smoothly on every device and connection, and so connected TV platforms can carry your channels. You should not have to think about the protocol itself; a good platform handles HLS and transcoding for you. Revidd transcodes uploaded content into multiple resolutions and outputs HLS, including the auto-generated HLS URL for each FAST channel.

Stream Smoothly to Every Device

Knowing what HLS is matters less than having a platform that outputs it correctly. If you want your content delivered with adaptive bitrate HLS so it plays well everywhere and your channels work on connected TV, book a demo and we will show how Revidd handles transcoding and delivery for you.

FAQ

What is HLS in simple terms?
HLS (HTTP Live Streaming) is a protocol that delivers video over the internet by breaking it into small segments and adjusting quality to each viewer's connection, so playback stays smooth across devices and network speeds.

What does HLS stand for?
HLS stands for HTTP Live Streaming. It was originally developed by Apple and is now a widely used standard for delivering streaming video to phones, computers, smart TVs, and streaming devices.

What is adaptive bitrate streaming?
Adaptive bitrate is the technique HLS uses to match video quality to a viewer's available bandwidth in real time. The content is encoded at several quality levels, and the player automatically chooses the best one that streams smoothly.

Why is HLS used for streaming?
Because it delivers reliably across devices and networks using standard web infrastructure, works through firewalls and CDNs, and uses adaptive bitrate to prevent buffering. It is also the format connected TV platforms expect to ingest.

What is the difference between HLS and DASH?
Both are adaptive bitrate protocols that segment video and switch quality by bandwidth. The key difference is device support: HLS plays natively on Apple devices and across the broad set of TVs and streaming sticks, while MPEG-DASH is an open standard with strong Android and web support but no native Apple playback.

Do I need to understand HLS to run a streaming service?
No. A good streaming platform handles HLS output and transcoding for you. You should know that your platform outputs adaptive bitrate HLS so content plays well everywhere, but you do not manage the protocol yourself.