There are hundreds of different tools used for different purposes. Some hackers are also talented programmers,
so they know how to build their own tools: either custom software for a specific vulnerability or generic tools
for a wide range of purposes.
The image below shows some of the tools you can use to monitor how well a Linux computer is running, to find
bottlenecks and issues. Some of these will give you valuable information about what is running on a system and
what you might exploit. Or they can themselves be abused to make an exploit.
To keep it simple, to keep the story moving, the tools used in your Toolkit are not named specifically. We just
refer to broad classes of tool and leave it to your imagination or to your later research to fill in the
details.
Sometimes you will see Technical Details boxes like this one, with extra technical information where we thought
it would help you understand a little more deeply. These boxes are always optional. There is nothing hidden in
them that will help you find the Donut Preferences Database. These boxes are for the curious, for the
explorers