The standard boot configuration of the Raspberry pi can lead to some characters not working properly on US keyboards. In particular, the shift-number characters like !,~,# can not be where you expect them. The easiest way to fix this is to edit the nano /etc/default/keyboard file. The following should fix things for you.
$ sudo nano /etc/default/keyboard
Then on the line for XKBLAYOUT change it to:
That should make your pi work properly with most US keyboards.
It is very easy to corrupt the SD card and your operating system on your Raspberry Pi. It is important to always properly shut down the raspberry pi. Never just remove power, always shutdown first. Never remove the SD card while the pi is booted or while it is powered. To remove the SD card, first shutdown the pi, then take the power off, then remove the card. Similarly, never plug the card in while the pi is powered.
The simplest way to shutdown the pi is with the command:
$ sudo halt
Instead, if you want to shutdown and then reboot, you can use:
$ sudo reboot
These two commands will take care of things most of the time. If for some reason sudo halt does not work, you can try the following:
In this lesson we explore a new and very powerful Linux command . . . the sort command. The sort command allows you to sort a file alphabetically, numerically or by calendar month. We show how to sort forward or backward, and how to send the sorted list either to a file or to the terminal window. This quick video will get you up to speed on sorting in Linux.
In this lesson we learn how to use the Linux wildcard. The wildcard allows you to automate what would otherwise be tedious tasks. The wildcard is the * character. For example, a command with *.txt would affect all files ending in .txt. Similarly, *.* would affect all files. You could also imagine dog*.txt would affect all files that start with “dog” and end with .txt. The video gives many examples of using the wildcard to simplify things.
Making The World a Better Place One High Tech Project at a Time. Enjoy!