Man command internally invokes the sed command to modify the contents of manual pages(documentation written for the commands) and delivers a user readable output.
To read documentation on sed command page-wise
/home/b3456/$ man sed | pg
suppose that you want to read the entire documentation of all the commands present in an unix environment and to save all of its pages in a single text file, you can run the following script from the command line to do so.
/home/b3456/$ cd /usr/bin
/usr/bin/$for i in `ls * `
>man $i >>/home/b3456/man_all.txt 2>/dev/null
Note: “>” symbol comes by default in all the lines
Here 2> indicates standard error.It is redirected to /dev/null(which is discarded)
Now you can take a print out of the text file you have just generated( make full use of office printer umm!!) and study all commands at home.