DOS 2.0 was developed to support the IBM PC/XT (introduced in March 1983), which came with 128K RAM standard, and models with 256K appeared soon enough. Even the older PCs could be upgraded with additional RAM, and DOS needed to have some mechanism to deal with that extra memory.
СюжетЛьготы ветеранам боевых действий:
。关于这个话题，搜狗输入法提供了深入分析
Interactive (local desktop)。体育直播对此有专业解读
FirstFT: the day's biggest stories