How to do it...

Open a terminal and run the following commands:

$ cat loremipsum.txt
$ head loremipsum.txt
$ head -n 1 loremipsum.txt
$ tail loremipsum.txt
$ tail -n 1 loremipsum.txt

Interestingly enough, the tail command has a feature that is different than the head command: it can monitor the tail end of a file forever until the command is exited or killed when using the -f or -F flags. Run the following command:

$ tail -F /var/log/kern.log

Keeping the tail command running, try disconnecting your wireless or Ethernet port. What do you see?

Press Ctrl + C to quit tail and run the following command:

$ more loremipsum.txt

Pressing the spacebar or Enter on your keyboard will progress through the file until the end. Pressing q will immediately exit more and return you to the console prompt.

Next, try the following command:

$ less loremipsum.txt 

Try navigating through the file using pg up, pg dn, the up and down arrow keys, and Enter and the spacebar. Notice anything?