Telephone

A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals that are transmitted via cables and other communication channels to another telephone which reproduces the sound to the receiving user. The term is derived from Greek: τῆλε (tēle, far) and φωνή (phōnē, voice), together meaning distant voice. A common short form of the term is phone.

In The Operative: No One Lives Forever
During the game Cate Archer sees a lot of telephones. In Assignment while she was taking a shower, Bruno Lawrie contacted to her. In Berlin by Night she was phoning her contact. In A Man of Influence one female employee was talking with her friend by telephone, making Cate undetected. In the beginning of Such Is the Nature of Revenge she used a telephone to tell Mr. Jones about succession of the mission.

External Link
Telephone on Wikipedia.