Even where seemingly no code appears, you can find some, e.g. klick the Smiley pictogram in implicitly-defined-regions-in-2d and copy ca. 1450 lines of code into a local file to have a look, here is where the smiley starts ...
FrameBox[
TagBox[GridBox[{
{"\"\<Smiley\>\""},
{
GraphicsBox[GraphicsComplexBox[CompressedData["
1:eJw1Vgs0lGkYRrqphMplKJRLVipNF5d4KeneUm6lkERRUglRErI2ojYRtppQ
IasNoZQ3t3E3MwYj4zozZkwxQ0u1hB2L75z//Oc55/mf93mf833v/6m7Xjh8
okay, it's compressed, so which page have you in mind?
