A "car telephone" typically refers to a mobile phone unit used within a vehicle. Though this term may still be used on occasion, there are many synonyms that are more commonly preferred today. For example, a "car phone" is widely utilized to explicitly describe the mobile phone designated for use in an automobile. Other popular alternatives include the term "mobile phone," "cell phone," or even "smartphone" depending on the device being used. Additionally, "hands-free device" or "in-car communication system" are other terms that can be used to describe a phone interface in a vehicle that allows for communication without distracting the driver.