Atlas had both virtual and protected memory.

Atlas 具有虚拟内存和受保护内存。

It also had advanced features Mac OS didn’t have, like program multitasking and protected memory.

它还具有 Mac OS 所没有的高级功能，例如程序多任务处理和受保护的内存。

First released in 1981, it became the most popular OS for early home computers, even though it lacked multitasking and protected memory.

它于 1981 年首次发布，成为早期家用计算机最流行的操作系统，尽管它缺乏多任务处理和受保护的内存。