Timefield is a Field API field that can store 3 types of time values: a simple time value, a start time and end time, or a combination of these two with a basic weekly repeat value. The values are stored in the database as integer offsets from 12AM. If the second value continues into the next day, i.e. 8PM - 2AM, the second value is stored as an offset +1 day. The goal of this field is to provide time storage that is not dependent on the Gregorian calendar.
Timefield module provides a field type 'timefield' with a default JQuery widget. The timefield can have an optional 'to time' and various input formats, depending on your preference. While this field is multi-value capable, I am not really sure about a use-case for this. There are a three display formatters, time (with optional to time, duration, and a mini-calendar output. You can configure various output formats in the format settings dialog option on the "Manage Display" section of the Field API UI.