Ключевые слова: blackboard, board, business, button, buy, buyer, chalk, chalkboard, click, concept, consumer, cursor, customer, design, discount, education, exchange, finance, finger, gesture, hand, icon, information, internet, join, label, link, mail, market, message, mouse, net, on line, page, pay, press, price, promotion, purchase, push, pushcart, retail, sale, sell, shop, sign, stock, store, symbol, technology, text, title, trade, web, www,