Full name is Central Standard Time
HNC – Heure Normale du Centre (French)
Email time zone indicator: -0600
An email sent from someone in the CST time zone will have the time zone listed as "-0600" in the headers of the email. (However, "-0600" does not have to be in CST, as other time zones could have the same UTC offset).
For actual dates DST might be observed, look at the examples below
Where and when is CST observed?
CST is used during winter in these US states (CDT during summer)
Alabama
Arkansas
Florida - North-West parts
Bay, Calhoun, Escambia, Holmes, Jackson, Okaloosa, Santa Rosa, Walton and Washington counties and norther Gulf county
Illinois
Indiana - these few north-western counties near Chicago
Lake, Porter, La Porte, Newton, Jasper, Starke
and these south-western counties in Indiana near Evansville
All except Arthur, Banner, Box Butte, Chase, Cheyenne, Dawes, Deuel, Dundy, Garden, Grant, Hooker, Keith, Kimball, Morrill, Perkins, Scotts Bluff, Sheridan, and Sioux counties and the western part of Cherry county which are on MST/MDT
North Dakota - North and Eastern parts
counties of Barnes, Benson, Bottineau, Burke, Burleigh, Cass, Cavalier, Dickey, Divide, Eddy, Emmons, Foster, Grand Forks, Griggs, Kidder, Lamoure, Logan, McHenry, McIntosh, McLean, Mountrail, Nelson, Oliver, Pembina, Pierce, Ramsey, Ransom, Renville, Richland, Rolette, Sargent, Sheridan, Steele, Stutsman, Towner, Traill, Walsh, Ward, Wells, Williams and northern parts of McKenzie and Dunn, westernmost part of Morton and Fort Yates in Sioux
Oklahoma
South Dakota - Eastern parts
counties of Aurora, Beadle, Bon Homme, Brookings, Brown, Brule, Buffalo, Campbell, Charles Mix, Clark, Clay, Codington, Davison, Day, Deuel, Douglas, Edmunds, Faulk, Grant, Gregory, Hamlin, Hand, Hanson, Hughes, Hutchinson, Hyde, Jerauld, Kingsbury, Lake, Lincoln, Lyman, Marshall, McCook, McPherson, Miner, Minnehaha, Moody, Potter, Roberts, Spink, Sanborn, Sully, Tripp, Turner, Union, Yankton, Walworth and eastern parts of Jones and Stanley