[lorax]

The bagel button makes only one side of the slot get hot (or at least makes one side hotter than the other). Your toaster probably has a bagel icon on the top showing you which way to put the bagel in (cut side towards the center in every toaster I have seen).

Source: I'm not married to toaster moguls but I do peer into operating toasters to see which wires turn red. Feel free to replicate my research and post your observations.

[sgarland]

Mine doesn’t have a bagel icon, but I do put them cut-side towards the center.

Looking closely during operation, the elements facing out from the center didn’t appear to change color with the bagel button depressed. It toasts the bagel just fine (as well as bread), though.

I should get a wattmeter and see if power draw changes.

[20after4]

My theory is that the bagel button does one thing only - it illuminates the bagel button when you press it. I've seen toasters with functional bagel mode but my latest cheap crap toaster does precisely nothing different when the bagel button is activated.

[dublin]

I don't think I've ever before been party to any conversation where the words "toaster mogul" ever appeared in the exchange, and yet, here they are, in all their golden brown and delicious glory!

[dzhiurgis]

Okay then. What does the frozen bread button do?

[lorax]

Ok, so that I didn't know. Here's from the Oster website: "When this feature is selected, the toaster will automatically defrost your food and then toast it in one easy step." So the temperature is lower for a little bit to thaw the food then higher to toast it.