0_Apprentice
Do you use headphones often?
1_Wizard
Yeah I do. I use them to convert electrical signals into sound. 
0_Apprentice
That's cool! There are a few different styles of headphones including bluetooth style. Are you familiar with those?
1_Wizard
Yes! There are also different types like the circumaural headphones while go over the head. 
0_Apprentice
Do you know how long headphones have been around?
1_Wizard
Yes! They were invented in the 19th century for telephone operators. 
0_Apprentice
That's right! I didn't realize how they were used for early telephone communications.
1_Wizard
Yeah that was to keep their hands free while they were working. 
0_Apprentice
Do you know when they started to become commercially popular for people?