Ubuntu镜像的arm64代表的是啥意思？
Like x86 and x64, ARM is a different processor (CPU) architecture. The ARM architecture is typically used to build CPUs for a mobile device, ARM64 is simply an extension or evolution of the ARM architecture that supports 64-bit processing. Devices built on the ARM64 architecture include desktop PCs, mobile devices, and some IoT Core devices (Rasperry Pi 2, Raspberry Pi 3, and DragonBoard). For example the Microsoft HoloLens 2 uses an ARM64 processor.
Maybe a little bit of correction on x86 and x64. Both x86 and x64 are same CPU architecture. HOW? x86 is a “CPU” architecture which was initially used with 16bit “chip” and later on extended to be used on 32 bit chip. For most of the time, we used a 32bit chip(each number represented with 32 bits) that had x86 architecture. So basically, when we said this computer (CPU) is x86, it meant 32 bit or vice versa and same with OS, if an OS was 32bit, then it meant it was running x86 CPU architecture chip. (I’m not considering ARM here) Now, due to the limitation of memory usage with 32bit chip that it can only support 4GB of RAM, x86 was then extended to be used on 64 bit chip, so basically now the same architecture (instructions set) was used to build a chip that used 64bit to represent a number, hence 64bit chip. Initially it was called x86-64 and later reduced to x64 which meant that x86 is the architecture on a 64bit chip.
所以，我的服务器的CPU是什么呢？
刚刚通过blos查看了，是intel的芯片，所以就意味着它是amd64位的。可以放心下载了。
注意区分arm64和amd64。
但是问题来了，桌面版和live-server区别是啥？
desktop是livecd+图形安装cd（可以直接从光盘读取进入系统然后在图形界面下安装）
server是服务器版（只装用命令行模式，没有图形部分，一般用户估计没怎么人用）
alternate是文本安装模式（安装过程用点中只能键盘操作，安装界面和windows前半段的类似）desktop和alternate安装完之后都带图形界面，一般用户用的，server是做服务器用的
我们是用来做深度学习的，不是用来挂web项目或者做云存储的。所以选择桌面版本。
下载镜像，清华内部还是用tuna下载比较快，外面下载速度应该也可以。
https://mirrors.tuna.tsinghua.edu.cn/ubuntu-releases/18.04/
后面按照这个链接完成启动盘的制作就好了
启动盘制作