Ubuntu官方推荐U盘镜像写入工具
官方文章参见：https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-windows?_ga=2.145079165.853971970.1540806080-1340574656.1540806080#1
windows推荐的是Rufus这款工具
Rufus官网：https://rufus.ie/en_IE.html
只有1m大小
具体使用方法参见官网文章：
https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-windows?_ga=2.145079165.853971970.1540806080-1340574656.1540806080#0
windowsRufus工具下载地址
windowsRufus工具绿色版下载地址
macos推荐的是
Disk Utility
Launch Disk Utility from Applications>Utilities or Spotlight search
具体使用方法参见：
https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-macos#0
ubuntu上使用镜像写入工具
Startup Disk Creator
具体使用方法参见：
https://tutorials.ubuntu.com/tutorial/tutorial-create-a-usb-stick-on-ubuntu#0