In engineering, you often run into issues of intellectual property - for example, patents, or trademarks. One thing to remember is that the research that you are publishing is also intellectual property - your own!
Just like with patents or trademarks, if you use others intellectual property, you have to acknowledge your use and provide citations and attributions. It's important to remember that as scholars and researchers, we take part in the scholarly conversation about the topics we are working on.
This means that if you are referencing ideas or original thoughts from others in your work, you have to provide attribution. Doing this not only acknowledges others work, but also places your research in context to what others have done before.
There are a variety of citation formats available for you to use. You may be familiar with a few like APA or MLA. One specific format for engineers to be aware of is IEEE Citation Style.
Below are some examples of IEEE Citation Style for popular formats:
These examples were adapted from the IEEE Reference Guide - there are more formats that are available in that guide