head [man page] - output the first part of files
head [OPTION]... [FILE]...
-c, --bytes=[-]N print the first N bytes of each file; with the leading `-', print all but the last N bytes of each file -n, --lines=[-]N print the first N lines instead of the first 10; with the leading `-', print all but the last N lines of each file
Command head will by default print first 10 lines of a file. Lets prove it by creating test file from /etc/services which contains line numbers.
$ cat /etc/services | nl > /tmp/services.txt
$ head /tmp/services.txt
with -n option we can instruct head command to print line numbers.
$ head -n /tmp/services.txt
make head command to print first 5 lines:
$ head -5 /tmp/services.txt
Same as with option -n with option -c we can print out number of bytes to the standard output. Lets do small test:
$ wc -l -c services.txt
$ head -c 22173 /tmp/services.txt | wc -l