Confused by abbreviations in your ancestors' military records? Here's a guide to some of the most common military alphabet soup:

AAA—Anti-aircraft Artillery

AB—Air Base

Abn.—Airborne

AD—Active Duty or Armored Division

AFB—Air Force Base

Armd—Armored

Arty.—Artillery

BB—Battleship (USN)

Bde.—Brigade

BG—Bombardment Group

Bn.—Battalion

Bty./Btry.—Battery

Cav.—Cavalry

Co./CO—Company/Commanding Officer

CONUS—Continental United States

Corp./Cpl.—Corporal

CV—Carrier

DD—Destroyer (USN)

Det.—Detachment

DOS—Date of Separation

EAD—Entered Active Duty (date)

FA—Field Artillery

FG—Fighter Group

G.I.—Government Issue

Gp.—Group

Inf.—Infantry

MCAS—Marine Corps Air Station

MIA—Missing in Action

MOS—Military Occupational Specialty

MP—Military Police

NAS—Naval Air Station

NMCB—Naval Mobile Construction Battalion

PCS—Permanent Change of Station

Pfc.—Private First Class

Plt.—Platoon

PO—Petty Officer

Pvt.—Private

PW/POW—Prisoner of War

QM—Quartermaster

Rcn.—Reconnaissance

RCT—Regimental Combat Team

Regt.—Regiment

Sgt.—Sergeant

Sig.—Signal

SN/SSN—Service Number/Social Security Number

Sq.—Squad or Squadron

TAD—Temporary Additional Duty

TAFMS—Total Active Federal Military Service (date)

TCG—Troop Carrier Group

TDY—Temporary Duty

USA—United States Army

USAAC/USAAF—United States Army Air Corps/ Army Air Force

USAF—United States Air Force

USMC—United States Marine Corps

USN—United States Navy

WIA—Wounded in Action