Linux: Head, Tail
Show first n lines
head filename- Show first n lines of a file. (most useful for big files, e.g. Log file.)
head -n 100 filename- Show first 100 lines of a file.
Show last n lines
tail filename- Show the last n lines of a file.
head -n 100 filename- Show last 100 lines of a file.
tail -f fname- View the last few lines of a growing file, updated continuously. Typically used on log files. Ctrl+c to exit.