function cHelpScreen(){
    this.init = false;
    this.iPage = 0;
    this.fSpeed = 0.9;
        
    this.show = function(){
        if ( !this.init ) {
            this.oBody = document.getElementsByTagName('body')[0];
            this.oHtml = document.getElementsByTagName('html')[0];  
            this.oContainer = document.getElementById('help_container');
            this.oContainer.style.display = "none";
            this.init = true;
        }
        
        try {
            oBody.style.overflow = 'hidden';
        } catch (e){ }
        try {
            oHtml.style.overflow = 'hidden';
        } catch (e){ } 
        
        this.oContainer.style.display = "";
        
        var aHtml = Array();

        this.createContainer(aHtml, 'top');
        
        aHtml.push('<iframe frameborder="0" scrolling="no" src="' + sBaseUrl + 'GeoStart/help/helpFrame.php?sColor=' + sColor + '" width="850" height="600" ></iframe>');
        
        
        this.createContainer(aHtml, 'bottom');
                
        this.oContainer.innerHTML = aHtml.join('');
        
        var size = checkSize();
        document.getElementById('help_overlay').style.height = size[1] + "px";
        
        
        resizer();
    }  
        
   
    this.hide = function(){
        if ( this.oContainer ) {
            this.oContainer.style.display = "none";    
        }
    }
    
    this.createContainer = function(aHtml, sPart){    
        switch ( sPart ) {
            case 'top':
                aHtml.push('<div id="help_overlay" onclick="oHelp.hide();" style="z-index:99997;height:100%;width:100%;background:#93a9b4;filter: alpha(opacity=50);opacity: 0.5;position:absolute;top:0;left:0;"></div>');
                aHtml.push('    <div id="help_draggable">');
                break;
            case 'bottom':            
                aHtml.push('    </div>');
                aHtml.push('</div>');
                break;
        }        
    }
}