- G Gigabyte
- g,d & r grinning, ducking and running
- GA Go Ahead
- GB GigaByte
- Gbps Gigabit per second
- GDI Graphical Device Interface
- GEM Graphics Environment Manager
- GHz GigaHerz
- GIF Graphics Interchange Format
- GIGO Garbage In Garbage Out
- GMR Giant Magneto-Resistive
- GNN Global Network Navigator
- GNU GNU is Not Unix
- GOSIP Government Open Systems Interconnection Profile
- GPF General Protection Fault
- GPR General Purpose Register
- GPR General-Purpose Registers
- GPS Global Positioning System
- GQL Graphical Query Language
- Grep Globally search for a Regular Expression and Print all lines containing it
- GSH Global School House
- GSM Global Standard for Mobile communications
- GUI Graphical User Interface