Ключевые слова: abstract, background, business, care, community, computer, concept, conceptual, crowd, design, family, freedom, group, guard, heart, home, house, human, icon, idea, illustration, isolated, key, keyhole, light, lock, love, man, mystery, network, people, person, protection, safe, safety, secret, security, shape, sign, social, symbol, technology, unlock, valentine, web, white, woman,