What does EPG mean on TVs?

Initials, acronyms and other jargon pose a barrier for people who are not in the know. For example, you know that TV means “television”, but what about an LCN or a PSIP. Do I need a new TV antenna for ATSC 3.0, and why are half of these terms only relevant to people with antennas? With all the shortcuts surrounding television, it can be difficult to decide where to start. Let’s start with our title: an EPG is an electronic program guide.

You may not remember picking up a “TV Guide” at the end of the supermarket checkout. But you may have seen a program generated by your smart TV, cable box or web page showing all the stations viewable in your area along with channel numbers, program schedules, show descriptions and content ratings. It’s an EPG.

Sometimes you’ll see the term IPG referring to guides that have interactive elements, such as self-navigation or the ability to make a la carte purchases, but this is now an obsolete distinction. EPG listing providers like Nielsen-owned Gracenote are responsible for ingesting information from stations, networks, and MVPDs (oh, we’ll get to that, too) and making sure it’s aggregated and displayed correctly to viewers in different regions. This is just the tip of the iceberg of TV acronyms.

Television channel numbers referred to specific frequency bands assigned by the Federal Communications Commission (FCC) that carried the audio and visual streams of a signal from an over-the-air transmitter to a receiving antenna. Channel allocations were spread across the country to ensure that the signal ranges of, for example, Channel 5 stations in different markets did not interfere with each other. At the turn of the century, stations adopted digital over-the-air (OTA) signals as part of the slow move toward high-definition broadcasting.

However, these signals were broadcast on channels that did not correspond to the analog channel number that the stations used to brand themselves. After all, channels are tied to frequencies and there is no way for analog and digital TV signals to share a set of frequencies simultaneously. To cope with this, the television industry has mobilized around technical standards for digital broadcasting. These standards incorporate PSIP, or Program and System Information Protocol, which dictates the structure of digital broadcast streams, including visible channels as well as EPG-type metadata.

PSIP introduced the concept of virtual channel numbers, also called logical channel numbers or LCNs. Basically, a station on analog channel 5 assigned to digital channel 20 could remap its digital location so that viewers with digital television antennas could access channel 5 on their remote and watch the station known as channel 5. The protocol also sets out standards on channel multiplexing so that viewers can access multiple program streams from the same station.

The development of television throughout the world has been relatively slow. Experimental transmissions through the mid-1920s slowed during the Great Depression. It was during World War II that radio and appliance companies banded together to form the National Television Standards Committee (NTSC). The NTSC developed and published technical specifications for analog broadcasts in 1941, which informed the FCC how to proceed in regulating television airwaves.

North American broadcasters followed the standard as well as a handful of adopted regions around the world that did not adopt the competing PAL and SECAM standards. The NTSC standard was changed for color output in 1953, at which point the industry began moving toward high-definition television and digital. This led to the creation of the Advanced Television Systems Committee (ATSC) in 1982, while the 1995 ATSC specification paved the way for digital broadcasting which included guidelines for HD picture parameters.

A new iteration would come in 2018 with ATSC 3.0, dubbed NextGen TV by marketers. Its benefits, such as 4K HDR viewing at up to 120 frames per second, interactive program elements without the need for external equipment and live reception on mobile phones, have not yet reached most viewers due to slow equipment turnover and content pipelines at the local and network levels. Speaking of high definition, we also delved into what HDMI means.

In the days before cord cutting, cable companies offered a greater selection of programming. Not so much today. The science of coaxial cable television delivery is quickly becoming obsolete, while the term “cable company” already is. In the case of regional provider WOW!, it stopped offering TV packages in 2023, requiring customers to connect their accounts to YouTube TV.

Whether satellite, cable or Internet, many in the industry now refer to pay TV operators as multichannel video program distributors, or MVPDs. Players like YouTube TV and Sling TV that maintain less infrastructure and don’t require special equipment on the viewer side tend to be called virtual MVPD (vMVPD). At the same time, free ad-supported streaming TV, or FAST, channels began populating social media, smart TV interfaces, YouTube and other free TV services like Tubi.

A FAST channel may seem self-explanatory, but the business decisions that result in cable channels like Music Television (MTV) airing endless repeats of the music video show “Ridiculousness” don’t apply here. Content owners can create channels based on a niche genre or even a single series if they have a comprehensive enough library. “The Price is Right: The Barker Era” and “The Price is Right” with Drew Carey are great examples.

We’ve had a lot to look at, but now let’s talk about the sound. Alongside NTSC, there was another Electronic Industries Association working group, the Broadcast Television Systems Committee (BTSC), which introduced stereophonic sound to the monophonic world of analog television in 1984. The BTSC Multichannel Television Sound (MTS) system, which eventually became part of the NTSC standard, was capable of using the broadcast spectrum available in each channel to run mono and stereo service, a rear channel for professional use, and second program audio, or SAP.

TV remotes used different labels to access this channel. While some would say SAP or MTS, others would use “Language” because an SAP often offered a dub of a program in a second language. SAPs sometimes broadcast an audio description feed – also known by its trade name Descriptive Video Service (DVS) – which was launched by the Media Access Group of state media powerhouse GBH. Visually impaired viewers could access a DVS and hear annotations on the existing soundtrack describing what was happening on screen.

In the digital age, ATSC uses Dolby compression technology to distribute simultaneous audio streams for a single program. ATSC 1.0 used Dolby Digital, more often called Dolby Audio Codec 3 or AC-3, while ATSC 3.0 used Dolby AC-4. The former brought 5.1 surround sound capability as the main improvement, while the latter can pump through a Dolby Atmos 7.1.4 setup. To learn more about this, we looked at the differences between Dolby Digital and Dolby Digital Plus.