Use source, documentation and experimentation to help you understand¶
When working towards an understanding of computers. Much software is open-source, and so can give you access to the code running beneath the software you run. When this isn't true, closed-source systems tend to have large amounts of high-quality documentation. When this isn't true, experimenting with the behaviour of something can give you surprisingly deep insights into how things work with enough curiosity. This is generally thought of as reverse-engineering.