Reach
Alexa reach rating for jahsonic.com
Definition
In the application of statistics to advertising and media analysis, reach is defined as the size of the audience who listen to, read, view or otherwise access a particular work in a given time period. Reach may be stated either as an absolute number, or as a fraction of a population.
For any given viewer, they have "reached" the work if they have viewed it at all during the specified time period. Multiple viewings by a single member of the audience in the cited time period do not increase reach.
Since reach is a time-dependent summary of aggregate audience behavior, reach figures are meaningless without a time period associated with them: an example of a valid reach figure would be to state that "[example website] had a one-day reach of 1565 per million on 21 March 2004". --http://en.wikipedia.org/wiki/Reach [Oct 2004]
Penetration (business) [...]
In business, penetration is often short for market penetration, the degree to which a product or service is known and/or used among potential customers. --http://en.wikipedia.org/wiki/Penetration [Oct 2004]Popularity [...]
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