User Agent String explained :
 Firefox 3.5.1 | |
|---|---|
| Mozilla | MozillaProductSlice. Claims to be a Mozilla based user agent, which is only true for Gecko browsers like Firefox and Netscape. For all other user agents it means 'Mozilla-compatible'. In modern browsers, this is only used for historical reasons. It has no real meaning anymore | 
| 5.0 | Mozilla version | 
| Windows | Platform | 
| U |  Security values: 
  | 
| Windows NT 5.1 | Operating System:   Windows XP | 
| en-US | Language Tag, indicates the language for which the client had been localized (e.g. menus and buttons in the user interface)  en-US =  English - United States | 
| rv:1.9.1.1 |  CVS Branch Tag The version of Gecko being used in the browser  | 
| Gecko | Gecko engine inside | 
| 20090715 |  Build Date: the date the browser was built  | 
| Firefox | Name :  Firefox | 
| 3.5.1 | Firefox version | 
| GTB5 | Google Toolbar 5 | 
| First visit: | 2009.07.23 09:29 | 
| Last visit: | 2018.07.29 01:22 | 
All Firefox user agent strings  | |
Firefox 3.5.1
 
English - United States