How are the spoken words transformed into text?

If it has to do with prerecorded material, the words are transcribed.
If it is necessary to carry out the process on a live broadcast, there are two possible ways:
• With a stenograph machine, which is a minimized key board designed for courtroom transcriptions. This device compensates for the speed limitations of a conventional keyboard, requiring high level skills.
• With voice recognition software programmed to recognize the unique vocal patterns of the person who ‘trains’ it. This method is not as precise as results generated by an expert steno-captioner.