User Agent String.Com 

User Agent String explained :

Opera 6.03
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
Linux 2.4.18-18.7.x i686	Operating System: Linux running on a Intel Pentium Pro CPU
U	Security values: N for no security U for strong security I for weak security
Opera	Name : Opera
6.03	Opera version
en	Language Tag, indicates the language for which the client had been localized (e.g. menus and buttons in the user interface) en = English
Last visit:	2014.02.12 03:17
All Opera user agent strings