Final answer:
When intruders break into a network, they often leave a trail behind, but skilled hackers may take steps to cover their tracks.
Step-by-step explanation:
When intruders break into a network, they often leave a trail behind. Hackers have a variety of methods to break into websites, to get people to click on links, and to lure people to give out information. However, skilled hackers may take steps to cover their tracks and make it difficult to trace their activities back to them.