HCS

• HCS clustering algorithm
• Hackensack Christian School
• Hajdu–Cheney syndrome
• Halifax Choral Society
• Hallett Cove School
• Halo Championship Series
• Hampshire Country School
• Hampton Christian Schools
• Hard-clad silica optical fiber
• Hardin County Schools
• Harlem Children Society
• Harrisburg Christian School
• Header check sequence
• Health-care System
• Heliospheric current sheet
• Hereford Cathedral School
• Heritage Christian School (disambiguation)
• Heritage College Sydney
• Hierarchical cell structure (telecommunications)
• Hierarchical constraint satisfaction
• High Council of State (disambiguation)
• High-content screening
• Highland Catholic School
• Hilltop Christian School
• Hinsdale Central School
• Holland Christian Schools
• Hollywood Center Studios
• Holy Cross School (disambiguation)
• Honoris Crux Silver
• Hooghly Collegiate School
• Horry County Schools
• Hub-center steering
• Hull Collegiate School
• Human chorionic somatomammotropin
• Hummocky cross-stratification
• Hyderabad Civil Service
• Hydrocortisone
• The Histochemical Society