Preload images
Preload images for use it with javascript or on a css rollover. Create one css style that uses this required images on a background and hiden them by a negative background position. This images will load on initial view of the page and stay ready on cache for future use.
Create one style and put the images
.preload-images {
background : url('images/img1.jpg') no-repeat -9999px -9999px,
url('images/img2.jpg') no-repeat -9999px -9999px,
url('images/img3.png') no-repeat -9999px -9999px,
url('images/img4.png') no-repeat -9999px -9999px;
}
Assign the style to one html tag
<body class="preload-images">