make
input id = inpu
button onclick = sendMsg()
div id = bodyMsg
code
function sendMsg() {
var Content_inp = document.getElementById("inpu").value;
var Content_div = document.getElementById("bodyMsg");
var d = new Date(); // for now
data = d.getHours()+":"+d.getMinutes()+":"+d.getSeconds();
Content_div.innerHTML += data+'<br>'+Content_inp +'<br>';
}