void demoshelp() {
   //
   new TCanvas("chelp","Help to run demos",200,10,700,500);

   TPaveText *welcome = new TPaveText(.1,.8,.9,.97);
   welcome->AddText("Welcome to the ROOT demos");
   welcome->SetTextFont(32);
   welcome->SetTextColor(4);
   welcome->SetFillColor(24);
   welcome->Draw();

   TPaveText *hdemo = new TPaveText(.05,.05,.95,.7);
   hdemo->SetTextAlign(12);
   hdemo->SetTextFont(52);
   hdemo->AddText("- Run demo hsimple.C first. Then in any order");
   hdemo->AddText("- Click left mouse button to execute one demo");
   hdemo->AddText("- Click right mouse button to see the title of the demo");
   hdemo->AddText("- Click on 'Close Bar' to exit from the demo menu");
   hdemo->AddText("- Select 'File/Print' to print a Postscript view of the canvas");
   hdemo->AddText("- You can execute a demo with the mouse or type commands");
   hdemo->AddText("- During the demo (try on this canvas) you can :");
   hdemo->AddText("  .... Use left button to move/grow/etc objects");
   hdemo->AddText("  .... Use middle button to pop overlapping objects");
   hdemo->AddText("  .... Use right button to get an object sensitive pop-up");
   hdemo->AddText(" ");
   hdemo->SetAllWith("....","color",2);
   hdemo->SetAllWith("....","font",72);
   hdemo->SetAllWith("....","size",0.04);

   hdemo->Draw();
}