write (in document.write) is a function not an array or an object, so you can't use [], you have tu use () :
document.write[], should be document.write() , and inside the paranthese yaou can put the string that you want to parse into the
html document:
Code:
<script>
var Digital=new Date()
var month=Digital.getMonth()
if (month <= 2){ // month is between jan and march
document.write("<IMG SRC='fieldworks/images/img5.jpg'>");
} else if (month <= 5){
// month is between april and june
document.write("<IMG SRC='fieldworks/images/img2.jpg'>");
} else if (month <= 8){ // july and september
document.write("<IMG SRC='fieldworks/images/img2.jpg'>");
} else { // otherwise its between oct and dec
document.write("<IMG SRC='fieldworks/images/img3.jpg'>");
}
</script>
But maybe you have a purpose in putting [Winter]...[Summer]-> can you explain?