wkhtmltopdf is command line tools to render HTML into PDF.
Real world example :
1 ) Like QA need to capture information in pdf or create sanity report than its very helpful to create pdf files.
2 ) E-commerce invoice created in html but you want to provide pdf invoice on there mail at that time it’s very useful.
wkhtmltopdf http://dilipprajapati.com htmltopdf.pdf
Refer : http://wkhtmltopdf.org/