> For the complete documentation index, see [llms.txt](https://docs.f5ezcode.in/cs-basic/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.f5ezcode.in/cs-basic/di-si-zhang-shi-jie-shi-zhi-zui-da-de-wu-jia-gong-si-du-shi-it-ju.md).

# 第四章－世界市值最大的五家公司，都是 IT 巨頭

- [4.1電腦與使用者的溝通橋樑：作業系統](https://docs.f5ezcode.in/cs-basic/di-si-zhang-shi-jie-shi-zhi-zui-da-de-wu-jia-gong-si-du-shi-it-ju/4.1-hang-jia-zhi-hui-xing-shou-bu-shi-iphone-jiu-shi-qi-ta.md)
- [4.2 硬體、韌體與軟體，別傻傻分不清楚！](https://docs.f5ezcode.in/cs-basic/di-si-zhang-shi-jie-shi-zhi-zui-da-de-wu-jia-gong-si-du-shi-it-ju/4.3-ying-ni-fen-de-qing.md)