Here's a script found on my site. 

```
var domains = ["abc.net", "abc.com", "abc.info", "abc.blogspot.com"];
if (domains.indexOf(document.location.hostname) == -1 && document.cookie.indexOf('opened=true') == -1) {
    window.top.location = "http://abc.net";
    document.cookie = "opened=true";
}

```

I don't know what it does but it always redirect to `abc.net`. Can somebody explain its working to me?