In Japan, South Korea, Argentina, and Brazil, the MSX was the preeminent home computer system of the 1980s. It was also fairly popular in continental Europe, especially in the Netherlands and Spain. Classrooms full of networked Yamaha MSX computers were used for teaching informatics in schools in some Arab countries, the Soviet Union, and Cuba, where they were widely used in public schools,[21] which allowed the Cuban government to educate students in computer subjects. In total, 9 million MSX computers were sold in Japan, making it relatively popular. However, the MSX did not become the worldwide standard envisioned because of limited adoption in other markets. Before the MSX's lack of success in these markets became apparent, US manufacturer Commodore Business Machines overhauled its product line in the early 1980s and introduced models such as the Plus/4 and Commodore 16 that were intended to better compete with the features of MSX computers.