To see inside the Pi.

How to set up the Pi from scratch:

Raspberry Pi Documentation – Getting started

Terminal icon is on top bar.

pi@frost:~ $ 

pi is my log-on name, and frost is the computer’s name.

You can make a directory called Fred by typing

mkdir /home/pi/fred <return>

To see into a directory

ls
(that is a lower case L) or better,
ls -la

you can see that fred is there

Get info from Pi.

pinout <return>
'pinout' displays really useful stuff, especially the pinout of the GPIO pins

Bash words: > and >>

The single greater than sign (>) in Bash is used to overwrite the contents of a file with the output of a command, while the double greater than signs (>>) append the output to the end of a file without deleting the existing content.

Use > command to overwrite the contents of a file with new data.

for example to replace the contents of alice.txt with the variable fred you go:

fred > /home/pi/alice.txt

and in case you want another copy of fred on the same file, you can use >> instead of >

The command cat gets data and prints it. on the screen e.g.

cat /proc/cpuinfo
cat /home/pi/aboutpi.txt

See: https://phoenixnap.com/kb/linux-cat-command for more info about cat

Useful sites:

Background stuff about using Terminal and the most useful commands https://www.freecodecamp.org/news/command-line-for-beginners/

How to get the Cheat Sheet of Bash commands: https://phoenixnap.com/kb/linux-commands-cheat-sheet

How to start using Terminal:  https://www.howtogeek.com/140679/beginner-geek-how-to-start-using-the-linux-terminal/

All about the filing system:          https://linuxhint.com/raspberry-pi-file-system/