A toaster uses infrared radiation to heat a piece of bread. When we put our bread in and see the coils glow red, the coils are producing infrared radiation. The radiation gently dries and chars the surface of the bread. The most common way for a toaster to create the infrared radiation is to use nichrome wire wrapped back and forth across a mica sheet like this.
Toaster Heating element, Nichrome wire and Mica sheet
Nichrome wire has a fairly high electrical resistance compared to something like copper wire, so even a short length of it has enough resistance to get quite hot. The nichrome alloy does not oxidize when heated. Iron wire would rust very quckly at the temperatures seen in a toaster. When we use it, a spring-loaded tray pops the toast out. This keeps us from having to turn the toaster upside down.
SPRING-LOADED TRAY(minor part)
Two mica/nichrome sheets line either side of the slot. A metal holder rises up and down in the slot to raise and lower the bread. Many toasters include a pair of grates on either side of the slot. The grates press againts the bread and center it. Two metal springs get pushed when the holder nears the bottom of the slot, and they pull the grates inward. The holders in each slot are connected to the handle that you depress to lower the bread into the toaster, as shown below:
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