Wikipedia defines Speech Recognition :

Speech recognition (in many contexts also known as 'automatic speech recognition', computer speech recognition or erroneously as Voice Recognition) is the process of converting a speech signal to a sequence of words, by means of an algorithm implemented as a computer program. Speech recognition applications that have emerged over the last years include voice dialing (e.g., Call home), call routing (e.g., I would like to make a collect call), simple data entry (e.g., entering a credit card number), and preparation of structured documents (e.g., a radiology report).

Voice recognition or speaker recognition is a related process that attempts to identify the person speaking, as opposed to what is being said.

Glossary of terms used in the speech and voice recognition industry.