For connecting data with template I use `Handlebars`

the code look like these

```

var data = {} // data from database

var template = fs.readFileSync('../templates/welcome.hbs').toString()l

var templateScript = Handlebars.compile(template);

var renderedHtml = templateScript(data);

// sent mail using custom function

sentMail(to,from,renderedHtml);

```