There are lots of different types of Engineers and engineering activities
Engineers design things and build things, like bridges, robots, computers, skyscrapers, or apps. Engineers sometimes invent things, like electric cars, Mars rovers, tablet computers, mobile phones, video-sharing apps, solar panels. Engineers might have to analyze something to figure out how it works. And, sometimes, engineers might have to figure out why something bad happened to something someone else built before.
Engineers use their knowledge and brainpower to solve problems
Some engineers are working on inventions to improve our world, like addressing climate change or increasing access to clean water. One example is the work that some people are doing to use cow farts and burps as an energy source. Cow farts and burps contain methane. Methane is a greenhouse gas that contributes to climate change. But, methane is also the principal component of natural gas, which we can use as an energy source. Using cow farts for energy: How cool is that?
Innovation means to come up with a brand new solution to a problem
Sometimes engineers experiment with things. Engineers invent new ways of using things that were invented before. Sometimes, they come up with new things that didn't exist, like the first time a working car was invented, or an airplane, or a cell phone. Those things didn't exist before - they had to be invented. Innovation is the introduction of something new, such as a new idea, method, or device.
Reverse Engineering is where you try to understand the design of something that you didn't build
Reverse Engineering means to study an already-built device or machine to understand its design, construction, or function - what it does, how it does it, and how it was made. Sometimes the person who built something isn't around, and you need to figure out how it works. Engineers might take it apart and look at its parts, and try to figure out what each one is, or does. They might do that in order to improve it, or fix it, or copy it - or maybe just to understand it.
Failure Analysis is where Engineers figure out why something failed, and what can be learned from it
Engineers want to know what went wrong with the machine or structure, so that it can be made safer. If a bridge collapsed, engineers will want to know if there was a design problem that might also be a problem with similar bridges elsewhere. They might have to evaluate a number of different possible causes, and determine the root cause for the failure. For example, for a bridge collapse, there might be a problem with some materials used for the bridge. Or, a specific part might have been built incorrectly, or designed badly. Or, the bridge might be in use beyond what it was designed for - for example, it might have become too heavy for its design. Or, the bridge may have needed some repairs or maintenance, perhaps due to cracks or wear, and no one had noticed or completed the work. Failure analysis is a series of steps to find the causes for failure in a product, device, or structure, and how to correct or prevent them.
Engineers are creative problem solvers, and there are lots of different different engineering fields
Civil Engineers build bridges or skyscrapers - but there may also be materials engineers involved as well. Aeronautical Engineers may build rockets or space shuttles or airplanes, but there may be Mechanical Engineers designing the seats or other internal components, and Computer Engineers or Controls engineers designing the software to help fly it and monitor all of the systems. Electrical Engineers design and build things related to electricity and energy. Computer Scientists create software programs - which we sometimes call apps. There are many types of engineering and many types of engineers.