the infamous hacker icon captain crunch helped to popularize usage of the blue box in the 70s, making at&t's long distance phone service affordable for the masses
a tone generator built and used by [phone phreaks] during the 70s to illegally obtain free telephone service by synthesizing audio dial tones used for controlling switching stations
"the infamous hacker icon captain crunch helped to popularize usage of the blue box in the 70s, making at&t's long distance phone service affordable for the masses" What is the definition of "blue box"?