全程mindmap,没有任何ppt；
并且，mindmap will be more perceptual than ppt;
循序渐进，不会被没学过的command stopped or kept from/hurdled/blocked;
只要和服务器打交道，都要学习Linux这门课程；作为程序员，不管是后端，嵌入式，大数据，运维or tester, we will interact with server more or less, which (Linux) is the fundament/base of programmer/coder or ITer,
At school, teacher usually only speaks 20 ~ 30 commands, not completed, then so this course can compensate/make the knowledge of Linux OS;
Computer(Science/technology/logic thinking/reasoning thinking) fans are strongly recommended to learn this course, to curd（check where is unknow, where needs to be updated, modified or clarified, etc）;
技不压身，more tehnoloiesskills，more supplement to our capabilities;