There are 25 time zones, all 15° in longtitude apart. All time zones are relative to Greenwich Mean Time, as measured in Greenwich, England. These are the standard, winter time, non-daylight savings, time zones.


GMT     Civilian                   Cities
----------------------------------------------------------------
+00:00  GMT (Greenwich Mean),    London, Dublin,
        UT(C), (Universal        Edinburgh, Lisbon,
            (Co-ordinated))        Reykjavik, Casablanca
        WET (Western European).
-01:00  WAT (West Africa)        Azores.
-02:00  AT (Azores)
-03:00                             Brazilia, Buenos Aires,
                                   Georgetown.
-04:00  AST (Atlantic Standard)  Caracas
-05:00  EST (Eastern Standard)   Bogoto, Lima, New York
-06:00  CST (Central Standard)   Mexico City, Saskatchewan
-07:00  MST (Mountain Standard)  
-08:00  PST (Pacific Standard)   Los Angeles
-09:00  YST (Yukon Standard)
-10:00  AHST (Alaska-Hawaii Standard)
        CAT (Central Alaska)
        HST (Hawaii Standard)
        EAST (East Australian Standard)
-11:00  NT (Nome)
-12:00  IDLW (International Date Line West)
+01:00  CET (Central European)   Paris, Berlin, Amsterdam,
        FWT (French Winter)      Brussels, Vienna, Madrid,
        MET (Middle European)    Rome, Bern, Stockholm, Oslo
        MEWT (Middle European Winter)
        SWT (Swedish Winter)
+02:00  EET (Eastern European,   Athens, Helsinki, Istanbul,
               Russia Zone 1)      Jerusalem, Harare, Zimbabwe
+03:00  BT (Baghdad, Russia      Kuwait, Nairobi, Riyadh,
              Zone 2)              Moscow
+04:00  ZP4 (Russia Zone 3)      Abu Dhabi, Muscat, Tblisi,
                                   Volgograd, Kabul
+05:00  ZP5 (Chesapeake Bay)
+06:00  ZP6 (Chesapeake Bay)
+07:00  WAST (Western Australian Standard)
+08:00  CCT (China Coast, Russia Zone 7)
+09:00  JST (Japan Standard, Russia Zone 8)
+10:00  GST (Guam Standard, Russia Zone 9)
+11:00 
+12:00  IDLE (International Date  Wellington, Fiji, 
                Line East)          Marshall Islands
        NZST (New Zealand Standard)
        NZT (New Zealand)
This nodeshell rescue was brought to you by Greenwich 2000 (which was utterly wrong about military time zones. see below)