Adicionando imagens - HTML

<!DOCTYPE html>
<html>
<head>
<title>Meu site</title>
</head>
<body>
<img src="http://s3.amazonaws.com/codecademy-blog/assets/f3a16fb6.jpg">
<img src="http://s3.amazonaws.com/codecademy-blog/assets/f3a16fb6.jpg">
</body>
</html>

Demo: http://jsfiddle.net/x3n010od/