If I am correct, I believe that all normal audio jacks (like the ones you have to your PC, traveling to your speakers) are analog.
Is there a way (perhaps with a high speed ADC) to convert it to digital on the fly? I am considering a project with Arduino (perhaps) where you capture audio in digital form and store it in an SD card.
Then of course, this will be just a sequence of bits. So is my project bound to failure because of the heavy volume of data? Or perhaps the information won't even make sense because it won't be equivalent with any audio format? Or essentially, it will be a WAV file (without the header)?
Finally, is there something like an analog to digital encoded (MP3 or whatever) hardware encoder?