From A for AGF Videoforschung to Z for zapping, the most important technical terms in video research are explained here.

Until the end of 2009, the negative list comprised broadcasters that could not be received anywhere by analogterrestrial means. It served the purpose of the correct assignment of reception levels according to the AGF definition.

Net coverage indicates the number of persons who have been reached at least once by a unit of video content (programme, advertisement, period of time, video). The calculation method for net coverage is mostly referred to as cumulation and frequency analysis. In this process, either the proportional weighted market share (p-value method) or the full weight (0/1 method with threshold value) of each person is applied. Each person can only be counted once.

Net cumulation refers to a method of cumulation and frequency analysis in which viewer growth is calculated across several programmes by means of net combination. Either the 0/1 method or the p-value method can be applied for calculating the performance values. Unlike summation of contact total, the persons included in net cumulation are only counted once in the calculation, regardless of how many programmes on the programme list they have watched.

The Nielsen Company is an international market research company that has its German headquarters in Frankfurt am Main. Nielsen is a service provider for AGF in the area of video streaming measurement.

Non-linear television refers to the use of television content independently of the broadcast time and programme flow. This can be done by using recording devices, with the aid of which content can be used later than the broadcast time (time-shifted viewing), or by means of an individual selection of content made available on the Internet independently of the broadcast time (VoD).

Non-linear video ads are a sub-category of in-stream video ads in which the advertising messages overlap a part of the video content. In this case, the ad placement is non-linear, meaning that it runs concurrently with the video content. Non-linear video ads are further sub-divided into overlay ads and branded players.

Non-TV households (previously: "internet-only households") refers to the population of private households with a German-speaking main income earner in which the following criteria are met: There is no TV set in use in the household, but at least one device with which online content can be received (PC, laptop, smartphone, tablet, games console).

In the fusion, non-TV households serve as recipients of the streaming use measured in the desktop panel or the mobile panel.

Non-users are a segment of persons differentiated from the reporting basis who have not watched a programme or several programmes. The viewing duration is equal to 0.

The number of cases fact refers to the unweighted number of persons or households on which an evaluation in the AGF Panel is based. It is directly related to the potential.

The number of videos indicates the number of different videos used from which a summary has been generated. The number of titles only includes those titles from the set of the total offering that have been used at least once in the evaluation period. Due to the different offering forms compared to conventional TV (playlists, short clips, different breakdown of long-form videos, etc.), the number of videos is not always comparable with programme titles in conventional TV.