High-quality thin films have been made by electron beam (EB) codeposition, sputtering, laser ablation, and most recently, chemical vapor deposition (CVD). The discovery of 30 K superconductivity in the La-Ba-Cu-O system and the subsequent dramatic increase in critical temperature (Tc) to 93 K in the Y-Ba-Cu-O (YBCO) system has led to an intense research effort to understand and expand on these results. This article focuses on different thin-film deposition techniques used to make superconducting films and discusses the properties and advantages of high- and low- Tc materials in a number of applications, including signal processing and analog electronic devices. The article provides information on superconducting materials, substrates, and buffer layers, and describes the major deposition techniques such as electron-beam coevaporation, sputtering, and laser ablation. The article also discusses in-situ film growth techniques used for producing atomic oxygen by radio frequency excitation or microwave discharge or with ozone.