Ключевые слова: abstract, black, business, call, caution, classic, communication, concept, contact, danger, danger sign, device, equipment, forest, graphic, icon, illustration, inform, information, label, marker, message, nature, old, outdoor, phone, pictogram, receiver, retro, road sign, sign, silhouette, speak, street sign, symbol, telephone, traffic sign, travel sign, voice, warning, warning label, web, yellow,