The profession of breaking things for a living. A test engineer's function within the work place is to document a well written procedure against a specification on how one may go about breaking something. The test engineer will then receive the thing to break and then test it against their procedure. If the item or device under test ("DUT") breaks, it does back to the developement phase for redesign. The test engineer's role within a company is to increase product quality and be a general nuisance of design engineers everywhere.
There are many different test methodologies for testing a product. One of the most common is referred to as, "black box testing." Black box testing is where the DUT is thought of as a device which receives a distinct set of inputs and generates a distinct set of outputs. For example, a black box test for a toaster would be to input toast into the toaster and expect the toaster to generate golden-brown toast as an output. If burnt toast is the output, and burnt toast is not within the specifications or test plan for the DUT. The test fails. However, if the output is wonderfully golden-brown flakey toast (and this type of toast is in the specification) the test shall pass.
Test engineers are applicable in every industry with in interest in quality control. Here are a few examples:
There are other types of Test Engineers, such as those that design test equipment to test product rather than testing the product directly themselves.