-NEMA 5-15
5-15 plugs are the standard three-prong plugs that you see in most commercial settings. They have two flat prongs for the hot and neutral wires and a round prong for the ground wire. These plugs are rated for 15 amps and 125 volts, making them suitable for a wide range of applications such as powering computers, office equipment, and small appliances.
You'll notice that one blade is larger than the other, which is meant to prevent the 5-15 from being inserted incorrectly. The large blade is the neutral wire, and the small blade is the hot wire.

Max Amperage: 15 amps
Max Voltage: 125 volts
Blades: Two vertical blades and one grounding pin

-NEMA 6-15
NEMA 6-15 plugs are also three-prong plugs but are designed for higher voltage applications. They have two flat prongs for the hot wires and a round prong for the ground wire. These plugs are rated for 15 amps and 250 volts, making them ideal for powering larger equipment like industrial machinery and power tools.
The NEMA 6-15 plug is commonly used in commercial kitchens for powering heavy-duty equipment such as commercial ovens, mixers, and grills that require higher voltage levels to operate efficiently. Industrial settings, such as manufacturing plants and workshops, also rely on the NEMA 6-15 plug to provide power to machinery and equipment that demand 240 volts for optimal performance.

Max Amperage: 15 amps
Max Voltage: 250 volts
Blades: Two horizontal blades and one grounding pin