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pre-roll also preroll

noun [countable]

a video advertisement that appears immediately before an online video

'Targeted video-on-demand versions of the films will further extend the fun along with pre-rolls that actively encourage people to skip the ad after Tesco Mobile's offers are covered in the first few seconds.'

The Drum 1st September 2014

If you're a regular viewer of online videos, then you'll certainly be familiar with the experience of having to twiddle your thumbs for a few seconds whilst some kind of advertisement plays out before you can get to the thing you're really interested in. What you may not know however, is that there's a name for this type of ad — it's called a pre-roll.

pre-roll advertisements have become much more common in recent years, possibly because they're assuming greater significance in an era when TV viewers are increasingly skipping advertising slots

A pre-roll is a promotional video that plays before the main video content the user has selected. In the unlikely event that you haven't seen one, then what happens is this: you click the play button on an online video of your choice and, instead of the thing you want to watch appearing, you're first presented with a video advertisement for a car, or home insurance, or the latest detergent, or … the possibilities are endless. A few moments later, after a pre-determined period of advertising has elapsed, you're finally able to watch what you were interested in.

Pre-rolls are often adaptations of television advertisements. They are generally shortened in length to 10 or 15 seconds, because the 30 seconds typical of TV ads is unsuitable when the video to be watched is often only a few minutes long itself. Pre-roll advertisements have become much more common in recent years, possibly because they're assuming greater significance in an era when TV viewers are increasingly skipping advertising slots completely by using digital technology to watch playbacks, or simply delay the start of a programme. Sometimes it's possible to skip pre-rolls, but usually only after the viewer has been compelled to watch them for at least a few seconds. To this end, a small display often appears in the corner of the screen counting down to the exact moment the viewer will be permitted to 'skip the ad'.

Background – pre-roll

Use of the term pre-roll in online advertising takes inspiration from the original sense of the word in the film industry, where pre-roll describes a period of time during which the camera rolls, but no action begins. The prefix pre- of course indicates 'before' (compare pre-war, precooked) and, correspondingly, it's also in fact possible to have mid-rolls, which appear sandwiched between two halves of the selected video, and post-rolls, which appear right at the end. Pre-rolls are the most common variation however, presumably because they're the only option which guarantees that no part of the video can be seen without watching at least some advertising.

Another relatively new term on the theme of controlling a user's browsing experience is the word paywall, which first appeared in the late nineties and refers to a webpage which prevents access to further pages on the same website until a fee is paid. Conventionally there are two kinds – a soft paywall, which limits what users can see without paying (e.g. samples only, or a fixed number of articles per month) and a hard paywall, which allows no access at all without payment of a subscription.

by Kerry Maxwell, author of Brave New Words

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Read last week's BuzzWord article. Sandwich generation.

This article was first published on 25th November 2014.

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a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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