Hermione took a deep breath, her eyes closed, and tried, desperately, to keep a hold on her temper. It wasn't as if it was Weasley's fault he didn't understand. Some muggles had trouble understanding technology let alone wizards.
"Okay, Hermione, I'll try again but this time I promise to take notes." Hermione saw, when she finally opened her eyes, that Weasley nodded his head encouragingly . She had been asking him to take notes all day but he had continually asserted he didn't need to, that he could remember how to on his own. He couldn't. Boys, they were all the same.
Hermione took another deep breath, flashed a quick smile and started again.
"This is called a computer, Mr Weasley. You turn it on like this…"