To detect the name/version of the web browser that has loaded an HTML page. Most often accomplished with Javascript or VBScript.
<script language=Javascript>
if(app.Name == 'Netscape')
{Alert('Using Netscape')}
by Steven Killick June 21, 2004
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Checking up on one's web surfing habits.
1. Reading the history of a person's web browser to see where they have been.

2. Pop-up advertising can be activated by active browser sniffing via spyware. The spyware senses that a person has searched for a term or that a term appears on a web page visited by the user and then a pop-up ad appears that is vaguely related to that term.

3. People that surf via unsecured wireless are likely to have their surfing sessions sniffed also.
by Brian K. June 21, 2004
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When an overly curious parent goes through their teenage child's search history, most often when looking for traces of pornography.
Mother: Have you been watching porn?

Son: Well, I gues you'll just have start browser sniffing to find out!
by BingGoogle January 5, 2011
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