The version of the open source Mozilla code base
being used in this browser.
This was not used
until Mozilla 0.9.2 (Netscape 6.1).
Optional Other Comments
This is space for custom implementations of Mozilla to
add in additional information.
The version of the Gecko rendering engine being used.
This is a date in the format
The name of the branded browser using the Mozilla
code. In Netscape 6 releases, this is Netscape6;
Netscape 7 changed it to just Netscape.
Application Product Version
The version of the branded browser using the Mozilla
In order to fully understand exactly what is going on, take a look at an example from Netscape 6.2.1 run-
ning on Windows XP:
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:0.9.4) Gecko/20011128
Matching up the various pieces of information:
Windows NT 5.1
Localization information is
It all seems pretty straightforward, right? Then why is MozillaVersion described as
for Netscape 6.0?
Although no one seems to be sure why this happened, it’s safe to assume that this is a holdover from
when the next planned version of Netscape was 5.0.
Netscape 7.1 was the last version of the Netscape-branded browser. AOL renewed its license agreement
with Microsoft to use Internet Explorer as the AOL software’s built-in browser and then it disbanded the
Netscape team. The Mozilla project still releases new versions of the browser on its own, along with a
friendlier version of Mozilla called Firefox.
Browser and Operating System Detection
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