The oscilloscope to the layman appears to be an esoteric scientific device but can easily be mastered and understood by anyone with basic AC and DC knowlege.
The oscilloscope displays the electromagnetic wave form of a signal. An oscilloscope can display voltage, current and phase information way down to microscale readings. Infact it is amazing but the average oscilloscope can also measure time down to the nano-second range, thats one billionth of a second. Oscilloscopes are used in the design and troubleshooting of circuits and components by electronics engineers.
All oscilloscopes used to consist of a cathode ray tube hence the acronym CRO "cathode ray oscilloscope" but today there are digital oscilloscopes also. These can be a portable standalone device known as a handheld oscilloscope, PC plugin cards or USB stand alone units that interface with a PC. Digital oscilloscopes often have advanced features such as spectrum analysis.
The most popular type of oscilloscope these days is the digital oscilloscope. Digital oscilloscopes can often interface with a computer. The older kind of oscilloscope, the analog variety is usually larger and heavier.
An intersting development for the hobbyist is the development of sound card oscilloscopes which work off the signal from a PC audio card. This is in its most basic form a software program that processes the signal. These programs are limited by the frequency range of the sound card which is seldom above the range of human hearing 20,000 hertz. There are hardware modifications available that can improve functionality.
Basic oscilloscope skills are taught in electrical trade school, high school physics and science and first year college papers. Allthough the oscilloscope may appear intimidating to the layman they are in fact very easy to use and understand. An oscilloscope is an essential piece of test equipment in any electrical or electronics lab.
A basic single channel oscilloscope can be purchsed quite cheaply but oscilloscopes wth better features can cost more than one thousand dollars.