To cost-effectively test embedded software, practitioners and researchers have proposed many test techniques, approaches, tools, and frameworks. However, obtaining an overview of the state of the art and state of the practice in this area is challenging for practitioners or new researchers. In addition, owing to an inadequate overview of what already exists in this area, some companies often reinvent the wheel by designing a test approach that's new to them but already exists. To address these problems, the authors conducted a systematic literature review of this area that covered the testing topics, testing activities, test artifacts, and industries on which the studies focused. The results can benefit both practitioners and researchers by serving as an index to the vast body of knowledge in this important, fast-growing area.