iPhone randomly saving homescreen images in photos

[IheartMyiPhone]

Hello fellow iPhone lovers!
I'm new to the MacRumors, so I apologize in advance if this question has been previously presented...I did a quick search just in case someone mentioned this before but no luck in finding any similar requests...
So, my iPhone has saved a total of 4 homescreen images in my Photos folder randomly. Two of which are just the homescreen itself, and then the other two are of e-mails.
Is this my phone or is this a common thing for these iPhones? I understand that the iPhone itself saves quick snapshot images to allow that shrinking or disappearing effect like when pressing the home button. Is that what this is related to?

 

[Wailord]

When you press the sleep/wake button and the home button it'll save a screenshot to your camera roll. It's possible that you're doing that on accident.

 

[TwelfthAG]

You are aware that the iPhone takes screenshots when you press the home button and the sleep/wake button at the same time, right?

 

[IheartMyiPhone]

Thanks!

Thanks! I actually was unaware of the 2 button thing, I must be doing that on accident or family members that play with my iphone do that from time to time! Or...there is still some mysterious way that it saves the screenshots. But at least now I know that there's a function capable of doing such!