Fur trade marten furs could generate in international markets spurred a "fur fever" in which many Russians moved to Siberia as independent trappers. From 1585 to 1680, tens of thousands of sable and other valuable pelts were obtained in Siberia each year. The primary way for the Muscovite state to obtain furs was by exacting a fur tribute from the Siberian natives, called a "yasak". "Yasak" was usually a fixed number of sable pelts which every male tribe member who was at least fifteen years old had to supply to Russian officials. Officials enforced "yasak" through coercion and by taking hostages, usually
PC Paintbrush before and since, "Paintbrush" version numbers were recorded with Roman numerals. Along with the release of "Paintbrush", ZSoft, following in the footsteps of "PCPaint"'s Pictor PIC format, the first popular image format for the PC, created the PCX image format. The first version of PC Paintbrush released in 1984 only allowed the use of a limited EGA 16-color palette. PC Paintbrush 3.10 was released in 1985. PC Paintbrush II was released in 1985. Another version was released in 1987 as Microsoft Paintbrush 2.0. PC Paintbrush 1.05 for Microsoft Windows was also released in 1987. PC Paintbrush III was released in