Hide or remove category tittle-name

One way to do this would be via CSS. If you look at your style.css file, around line 416 you’ll see

.pinbin-category {
  display: none; /*add this line here*/
  position: absolute;
  width: auto;
  background: #000;
  zoom: 1;
  filter: alpha(opacity=70);
  -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=70)";
  filter: alpha(opacity=70);
  opacity: 0.7;
  margin-top: -36px;
  z-index: 1;
  height: 30px;
  overflow: hidden;
  left: 0;
}

Should you want the category text to reappear you would then just remove the line you’re adding. Hope this helps.