内部存储空间 手机存储空间 sd卡

有些手机（如MTK平台）分内部存储空间和手机存储空间，据说内部存储空间只是给装软件用的，而手机存储空间类似内置的SD卡，这样分经常导致安装软件时，明明有空间，但是还是装不下。请问为什么要这样分呢？有什么好处和坏处？而其他平台手机大多都是只分为一大块存储空间，如三星索尼等，没有内部存储空间和手机存储空间之分，安装软件和放照片都OK。

早期的安卓系统设计了两块用户可用的存储空间，即：

/data分区：所谓“内部存储空间”，可以装app，也可以保存app的数据，但用户不能用它保存自己的文件（比如照片/视频/音乐等）

/sdcard分区：加载一张可移除的SD存储卡，可以装app，可以保存app的数据，也可以供用户保存自己的文件
后来有一些厂商开始在手机里内置一块EMMC存储卡，分成若干分区，/data分区和/sdcard分区都是从上面划分出来的，这时/sdcard分区会显示成“手机存储空间”，但这两个分区的作用没有变化。为了继续支持SD卡，有的厂商会扩展安卓系统，比如索尼增加了一个/ext_card分区用于加载SD卡。

再后来有些厂商开始觉悟，做出了合并/data分区和/sdcard分区的方案，即只从EMMC卡上分一个/data分区，然后它的某个子目录虚拟成/sdcard分区，这样的话/data和/sdcard共享空间，可供保存文件的存储空间更大了。

安卓自版本4.2开始，提供了这种虚拟分区的内置支持，相信会有越来越多的手机支持这个特性。

安卓系统分区介绍：

英文原文：Android Partitions
Explained: boot, system, recovery, data, cache & misc  地址：
安卓手机和平板一般包括以下标准内部分区：

/boot

/system

/recovery

/data

/cache

/misc

另外还与SD卡分区：

/sdcard

/sd-ext

现中英文对照如下：

注意，只有/sdcard在所有安卓设备豆油。其它只在部分设备中有。下面看一下各个分区的内容和作用。

Note that only /sdcard
is found in all Android devices and the rest are present only in select devices. Let’s now take a look at the purpose and contents of each of these partitions.
/boot

正如名字所代表的意思（注：boot的意思是启动），这个分区使手机可以启动。它包括了内核（kerne）和ramdisk两部分。如果没有这个分区，手机通常无法启动到安卓系统。只有必要的时候，才去通过Recovery软件擦除（format）这个分区，一旦擦除，设备只有再从新安装一个新的boot分区，可以通过安装一个包含boot分区的ROM来实现，否则无法启动安卓系统。

This is the partition
that enables the phone to boot, as the name suggests. It includes the kernel and the ramdisk. Without this partition, the device will simply not be able to boot. Wiping this partition from recovery
should only be done if absolutely required and once done, the device must NOT be rebooted before installing a new one, which can be done by installing a ROM that includes a /boot partition.
/system

这个分区基本包含了整个安卓操作系统，除了内核（kerne）和ramdisk。包括安卓用户界面、和所有预装的系统应用程序。擦除这个分区，会删除真个安卓系统，但不会导致不能启动。你可以通过进入Recovery程序或者bootloader程序中，安装一个新ROM，也就是新安卓系统。

This partition basically
contains the entire operating system, other than the kernel and the ramdisk. This includes the Android user interface as well as all the system applications that come pre-installed on the device. Wiping this partition will remove Android from the device without
rendering it unbootable, and you will still be able to put the phone into recovery or bootloader mode to install a new ROM.
/recovery

这个分区可以认为是一个boot分区的替代品，可以是你的手机进入Recovery程序，进行高级恢复或安卓系统维护工作。要更详细的了解这个分区，请参考CWM使用指南。

The recovery partition
can be considered as an alternative boot partition that lets you boot the device into a recovery console for performing advanced recovery and maintenance operations on it. To learn more about this partition and its contents, see the ‘About Android Recovery’
section of our guide to ClockworkMod recovery
/data

这个分区也叫用户数据区，包含了用户的数据：联系人、短信、设置、用户安装的程序。擦除这个分区，本质上等同于手机恢复出厂设置，也就是手机系统第一次启动时的状态，或者是最后一次安装官方或第三方ROM后的状态。在Recovery程序中进行的“data/factory
reset ”操作就是在擦除这个分区。

Also called userdata,
the data partition contains the user’s data – this is where your contacts, messages, settings and apps that you have installed go. Wiping this partition essentially performs a factory reset on your device, restoring it to the way it was when you first booted
it, or the way it was after the last official or custom ROM installation. When you perform a wipe data/factory reset from recovery, it is this partition that you are wiping.
/cache

这个分区是安卓系统缓存区，保存系统最常访问的数据和应用程序。擦除这个分区，不会影响个人数据，只是删除了这个分区中已经保存的缓存内容，缓存内容会在后续手机使用过程中重新自动生成。

This is the partition
where Android stores frequently accessed data and app components. Wiping the cache doesn’t effect your personal data but simply gets rid of the existing data there, which gets automatically rebuilt as you continue using the device.
/misc

这个分区包括了一些杂项内容：比如一些系统设置和系统功能启用禁用设置。这些设置包括CID(运营商或区域识别码）、USB设置和一些硬件设置等等。这是一个很重要的分区，如果此分区损坏或者部分数据丢失，手机的一些特定功能可能不能正常工作。

This partition contains
miscellaneous system settings in form of on/off switches. These settings may include CID (Carrier or Region ID), USB configuration and certain hardware settings etc. This is an important partition and if it is corrupt or missing, several of the device’s features
will will not function normally.
/sdcard

这个分区不是设备系统存储空间，是SD卡空间。从使用上讲，这个是你自己的存储空间，可以随便你任意存放相片、视频、文档、ROM安装包等。擦除这个分区是完全安全的，只要你把分区中你需要的数据都备份到了你的电脑中。虽然一些用户安装的程序会使用这个分区保存它的数据和设置信息，擦除了这个分区，这些程序的数据，比如有些游戏的存档，就会全部丢失。在既有内部SD卡和外部SD卡的设备中，比如三星Galaxy
S和一些平板电脑，/sdcard分区通常指向内部SD卡。外部SD卡，如果存在的话，会对应一个新的分区，每个设备都不一样。在三星Galaxy S手机中， /sdcard/sd代表的是外部SD卡，而其它设备，有可能是/sdcard2。与/sdcard不同，没有系统或应用程序数据会自动存放在外部SD卡中。外部SD卡中的所有数据都是用户自己添加进去的。在你把分区中需要的数据都备份到了你的电脑中之后，你可以安全的擦除这个分区。

This is not a partition
on the internal memory of the device but rather the SD card. In terms of usage, this is your storage space to use as you see fit, to store your media, documents, ROMs etc. on it. Wiping it is perfectly safe as long as you backup all the data you require from
it, to your computer first. Though several user-installed apps save their data and settings on the SD card and wiping this partition will make you lose all that data.On devices with both an internal and an external SD card – devices like the Samsung Galaxy
S and several tablets – the /sdcard partition is always used to refer to the internal SD card. For the external SD card – if present – an alternative partition is used, which differs from device to device. In case of Samsung Galaxy S series devices, it is
/sdcard/sd while in many other devices, it is /sdcard2. Unlike /sdcard, no system or app data whatsoever is stored automatically on this external SD card and everything present on it has been added there by the user. You can safely wipe it after backing up
any data from it that you need to save.
/sd-ext

这不是安卓系统的标准分区，但在第三方ROM届却很流行。它根本上是你SD卡上一个额外的分区，从外部功能表现上，与
/data分区的功能相同。一些第三方ROM，有一些特殊的功能叫做APP2SD+或者data2ext。这个功能在设备的内部存储空间比较小（也就是分配给/data分区的空间比较小）时非常有用。因此，需要安装更多程序，但内部空间又不够的用户，可以使用支持这个功能的第三方ROM，来获取额外的空间安装更多的应用程序。 擦除这个分区和擦除 /data分区的结果相同，你将会丢失联系人，短信、安装应用程序和设置。

This is not a standard
Android partition, but has become popular in the custom ROM scene. It is basically an additional partition on your SD card that acts as the /data partition when used with certain ROMs that have special features called APP2SD+ or data2ext enabled. It is especially
useful on devices with little internal memory allotted to the /data partition. Thus, users who want to install more programs than the internal memory allows can make this partition and use it with a custom ROM that supports this feature, to get additional
storage for installing their apps. Wiping this partition is essentially the same as wiping the /data partition – you lose your contacts, SMS, market apps and settings.

到此，就结束了安卓各个分区的介绍。现在如果安装一个ROM时，安装前要求你擦除某个分区，你应该更加了解你要进行的操作的作用和结果，也知道你会丢失那些内容，而那些内容又不会丢失。你也知道应该备份那些内容，而那些又不需要备份。

With this, we conclude
our tour of Android partitions. Now whenever you install a ROM or mod that requires you to wipe certain partitions before the installation, you should be in a better position to know what you’re losing and what not and thus, you’ll know what to backup and
what not.