Clock

<html>

<canvas id="gameCanvas" width="1350" height="640"></canvas>

<script>

var second = 0
var minute = 0
var hour = 0

var paused = false

function countSec() {
second ++
}

function countMin() {
                if(second == 60) {
                                second = 0;
                                minute ++
                }
}

function countHour() {
                if(minute == 60) {
                                minute = 0;
                                hour ++
                }
}

window.onload = function() {
                canvas = document.getElementById('gameCanvas');
                canvasContext = canvas.getContext('2d');

                var framesPerSecond = 1
                setInterval(function() {
                drawCounter();
                if(paused == false) {
                    countSec();
                    countMin();
                    countHour();
                }
                }, 1000/framesPerSecond);

                canvas.addEventListener('mousedown',handleMouseClick);
}

function drawCounter() {
                drawRect(0,0, 750,750, 'white');
                canvasContext.font="40px Arial";
                canvasContext.fillStyle = 'blue';

                canvasContext.fillText("Seconds", 50,50);
                canvasContext.fillText(second, 230,50);

                canvasContext.fillText("Minutes", 50,100);
                canvasContext.fillText(minute, 230,100);

                canvasContext.fillText("Hours", 50,150);
                canvasContext.fillText(hour, 230,150);

                canvasContext.fillText(":", 215,50);
                canvasContext.fillText(":", 215,100);
                canvasContext.fillText(":", 215,150);
}

function drawRect(leftX, topY, width, height, drawColor) {
                 canvasContext.fillStyle = drawColor;
                 canvasContext.fillRect(leftX, topY, width, height);
}

function handleMouseClick(evt) {
                if(paused == false) {
                             paused = true
                } else if(paused) {
                             paused = false
                }
}

</script>

<html>