Type B vs. Type G

Type B adds a round grounding pin to Type A's two flat blades -- NEMA 5-15, the most common outlet in North America. The ground pin is deliberately longer than the power blades, so it connects before and disconnects after them, a safety-sequencing feature shared with several other grounded plug types worldwide.

Type G, the British standard (BS 1363, 1947), is the only common plug type with a fuse built into every single plug -- protecting the appliance's cord, not just the household circuit. It's used across the UK, Ireland, Hong Kong, Singapore, Malaysia, and much of the Gulf.