2012/08/04 Edited by：xuzhezhao Last edited：2012/08/04
1. 如果只有 電腦上只安裝了一個系統，則默認不會顯示啓動菜單。
2. 按住shift或者在某些情況下按住esc來顯示啓動菜單。
3. 沒有了/boot/grub/menu.lst，該文件被/boot/grub/grub.cfg取代。
4. There is no "/find boot/grub/stage1" at the grub prompt. Stage 1.5 has been eliminated。
5. 主要配置文件是/boot/grub/grub.cfg。
6. grub.cfg文件被update-grub更新。
7. 可用的內核都會被自動添加到啓動菜單，當執行update-grub命令時。
8. 當用戶想要創建一個啓動項時，可以編輯/etc/grub.d/40.custom文件。
9. 啓動菜單顯示配置的主要文件是/etc/default/grub。
10. 配置啓動菜單的配置文件有很多，除了/etc/default/grub外，還有/etc/grub.d/目錄中的文件。
11. 分區（partition）的表示數字不是從0 開始了，而是從1開始了。設備號沒有變，第一個設備還是用hd0表示，在/boot/grub/device.map(自己新建吧要)可以指定設備的表示名稱。
12. 當執行update-grub時，自動搜索其他的操作系統，如windows，搜索到的操作系統會自動添加到grub的啓動菜單中。
13. 改變配置文件之後，要執行update-grub才使新的配置生效。
原文：
RUB 2's default menu will look familiar to GRUB users but there are a great number of differences beneath the surface.
1. On a new installation of Ubuntu 9.10 or later with no other installed operating systems, GRUB 2 will boot directly to the login prompt or Desktop. No menu will be displayed.
2. Hold down SHIFT to display the menu during boot. In certain cases, pressing the ESC key may also display the menu.
3. No /boot/grub/menu.lst. It has been replaced by /boot/grub/grub.cfg.
4. There is no "/find boot/grub/stage1" at the grub prompt. Stage 1.5 has been eliminated.
5. The main Grub 2 configuration file, normally located in the /boot/grub folder, is grub.cfg. It is the product of various scripts and should not normally be edited directly.
6. grub.cfg is overwritten by certain Grub 2 package updates, whenever a kernel is added or removed, or when the user runs update-grub.
7. The menu list of available Linux kernels is automatically generated by running update-grub.
8. The user can create a custom file in which the user can place his own menu entries. This file will not be overwritten. By default, a custom file named 40_custom is available for use in the /etc/grub.d folder.
9. The primary configuration file for changing menu display settings is called grub and by default is located in the /etc/default folder.
10. There are multiple files for configuring the menu - /etc/default/grub mentioned above, and all the files in the /etc/grub.d/ directory.
11. Partition numbering has changed. The first partition is now 1 rather than 0. The first device/drive is still hd0 by default (no change). These designations can be altered if necessary in the device.map file in the /boot/grub folder.
12. Automated searches for other operating systems, such as Windows, are accomplished whenever update-grub is executed. Operating systems found will be placed in the Grub 2 menu.
13. Changes made in the configuration files will not take effect until the update-grub command is executed.