jsfiddle.net/65Ggv/16
PS: Картинки из гугла по запросу cat icon
//Большая картинка
<img id="dev" src="https://image.freepik.com/free-icon/no-translate-detected_318-52837.jpg"/>
//мелкие картинки
<img onclick="imgCH(this);" src="https://cdn1.iconfinder.com/data/icons/animals-18/154/cat-seat-skin-body-animal-512.png">
<img onclick="imgCH(this);" src="http://icons.iconarchive.com/icons/sonya/swarm/256/Cat-icon.png">
<img onclick="imgCH(this);" src="https://d30y9cdsu7xlg0.cloudfront.net/png/1836-200.png">
function imgCH(imgDIV)
{
document.getElementById("dev").src = imgDIV.src;
}
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Для background-image:
HTML:
<img id="dev" style="background-size: cover; background-image: url(https://image.freepik.com/free-icon/no-translate-detected_318-52837.jpg);"/>
<img onclick="imgCH(this);" style="background-size: cover; background-image: url(https://cdn1.iconfinder.com/data/icons/animals-18/154/cat-seat-skin-body-animal-512.png);">
<img onclick="imgCH(this);" style="background-size: cover; background-image: url(http://icons.iconarchive.com/icons/sonya/swarm/256/Cat-icon.png);">
<img onclick="imgCH(this);" style="background-size: cover; background-image: url(https://d30y9cdsu7xlg0.cloudfront.net/png/1836-200.png)">
JS
function imgCH(imgDIV)
{
document.getElementById("dev").style.backgroundImage = imgDIV.style.backgroundImage;
}