These work on WebVPython only

console.log()

It is possible to output text and variable values to the JavaScript console. In a browser press CTRL-J to open the console.

console.log('A scalar', a+10, 'and a vector', v.toString())

alert()

An alert pauses execution and displays the string in a dialog box. Numeric values are converted to strings.

alert('The mass is '+m+' kg.')