The Equipment Protector
It looks like a resistor except it has a line through it which represents the filament.
There you can see the filament.
A Fuse in a Circuit
The fuse is in a circuit just like any other component.
A Broken Fuse
This Fuse has saved a bulb. The filament is broken and the Fuse needs to be replaced.
Fuse in a Plug
The black arrow points to where to fuse is in this plug. It will cut the circuit if the current is too high.