js-- debugging common statement

<! DOCTYPE HTML > 
< HTML > 
    < head > 
        < Meta charset = "UTF-. 8" > 
        < title > </ title > 
    </ head > 
    < body > 
        < Script type = "text / JavaScript" > 
            / * 
             Control browser pop up a warning box 
             * * / 
            alert ( " test 1 " );
            / * 
             Let the computer outputs a contents page 
             * * / 
            document.write ( "Page display form " );
             / * 
             output content to a console 
             * * / 
            the console.log ( " console output " );
         </ Script > 
    </ body > 
</ HTML >