Some important softwares....

#To read Linux info documentation in colors
apt-get install pinfo
pinfo page
pinfo grep

#To show difference in colors
yum install colordiff
sudo apt-get install colordiff

colordiff file1 file2
diff -u file1 file2 | colordiff
diff -u file1 file2 | colordiff | less -R
diff file1 file2 | remark /usr/share/regex-markup/diff

grc diff file1 file2

#To convert HTML to pdf
sudo apt-get install wkhtmltopdf
sudo ln -s /usr/bin/wkhtmltopdf /usr/local/bin/html2pdf