Library of Congress Classification System
U - Military Science
| U | 1-900 | Military Science (General). |
| 21-22.3 | War, Philosophy, Military Sociology | |
| 27-43 | History of Military Science | |
| 164-167.5 | Tactics | |
| 250-225 | Maneuvers (Combined Arms) | |
| 320-325 | Physical Training of Soldiers | |
| 400-714 | Military Education and Training | |
| 750-773 | Military Life, Manners, and Customs | |
| 799-897 | History of Arms and Armor | |
| UA | 10-997 | Armies: Organization, Description, Facilities, etc. |
| 21-880 | By Region or Country | |
| 910-915 | Mobilization | |
| 926-927 | Civil Defense | |
| 929.5-929.95 | War Damage in Industry, Industrial Defense | |
| 940-945 | Military Communications | |
| 985-997 | Military Geography | |
| UB | 1-900 | Military Administration. |
| 320-338 | Enlistment, Recruiting, Placement, Promotion, Discharge, etc. | |
| 340-345 | Compulsory Service | |
| 356-369.5 | Provision for Veterans | |
| 380-385 | Soldiers' and Saliors' Homes | |
| 410-415 | Officers | |
| 416-419 | Minorities, Women, etc. in Armed Forces | |
| UC | 10-780 | Maintenance and Transportation. |
| 20-258 | Organization of the Service | |
| 260-267 | Supplies and Stores | |
| 270-360 | Transportation | |
| 400-440 | Barracks, Quarters, Camps | |
| 460-535 | Clothing and Equipment | |
| 600-695 | Horses, Mules, Remount Service | |
| 700-780 | Subsistence | |
| UD | 1-495 | Infantry. |
| 157-302 | Tactics, Maneuvers, Drill Regulations | |
| 380-425 | Small Arms | |
| 480-485 | Airborne Troopes, Parachute Troops | |
| 490-495 | Airmobile Operations | |
| UE | 1-500 | Cavalry, Armored and Mechanized Cavalry. |
| 157-302 | Tactics, Maneuvers, Drill Regulations | |
| 460-475 | Horses | |
| UF | 1-910 | Artillery. |
| 157-302 | Tactics, Maneuvers, Drill Regulations | |
| 400-405 | Field Artillery | |
| 520-537 | Ordnance and Small Arms | |
| 540-545 | Arsenals, Magazines, Armories, etc. | |
| 560-780 | Ordnance Material (Ordnance Proper) | |
| 820-830 | Ballistics, Velocities and Motions of Projectiles | |
| UG | 1-1530 | Military Engineering, Air Forces, Air Warfare |
| 1-620 | Military Engineering (including fortification, chemical warfare, signaling) | |
| 160-302 | Tactics and Regulations | |
| 360-390 | Field Engineering | |
| 410-442 | Fortifications and Defenses, By Region of Country | |
| 443-449 | Attack and Defense, Siege Warfare | |
| 470-474 | Military Surveying, Topography, and Mapping | |
| 500-565 | Technical Troops and Other Special Corps | |
| 570-582 | Military Signaling | |
| 590-613.5 | Military Telegraphy and Telephony | |
| 622-1530 | Air Forces, Air Warfare | |
| 633-635 | By Region or Country | |
| 637-639 | Education and Training | |
| 770-1045 | Organization, Personnel Management | |
| 1097 | Air Bases | |
| 1100-1435 | Equipment and Supplies | |
| 1240-1245 | Airplanes | |
| 1500-1530 | Military Astronautics, Space Warfare | |
| UH | 20-910 | Other Military Services. |
| 20-25 | Chaplains | |
| 201-485 | Medical and Sanitary Service | |
| 520-560 | Care of Sick and Wounded | |
| 750-769 | Military Social Work, Social Welfare Services | |
| 800-910 | Recreation and Information Services |
To the Library of Congress Classification index

