引用:
BTW：有网友转贴贴了国外某网站的关于四种BootLoader版本的英文原文说明，然后用电脑软件翻译生成的中文，翻译软件译的很差， ”xlc0212“网友人工翻译了这个英文说明，但是在原帖的第二页，不便大家浏览，我把它重新转贴出，虽然翻译的还不是很完美，但比软件翻译的要好多了。
期待”weip外翻组“来完美翻译。
在此，感谢”xlc0212“的翻译！
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中、英文对照文章如下：
Right now there are 4 different Bootloaders, [yes you read right 4]. These are:
现在又4种BL（是的，4种）。这些是：
1. Bootloader 3.9
2. Bootloader 4.6
3. Bootloader 3.9 Fakeblank
4. Bootloader 3.8 (Recent appearance)
Now, I'll explain a bit more on these different bootloaders.
现在，我要解释点这些的区别
Bootloader 3.9 was the first bootloader to be used on iPhones that were made on week 45 or earlier in 2007. This Bootloader [3.9] allows the iPhone SimFree (IPSF) paid unlock aswell as GeHot's IPSF-like free unlock. Also, this bootloader allows you to downgrade your Baseband (which controls your Wi-Fi, EDGE and Calls) firmware. Downgrading baseband is useful when you updated by mistake or/and want to go back down to a previous iPhone firmware. Bootloader 3.9 does not allow bootloader update
BL3.9是最新的BL，45周前或07年较早的IP上都有用上，这个BL3.9允许IP收费软解锁（IPSF），和GeHot的IPSF-like（像IPSF）的免费解锁一样好。同时，这个BL允许你降级你的BB（控制你WIFI，EDGE，和电话的）固件。降级BB是很有用的当你在升级出现失误（变砖）或像降级固件。BL3.9不允许BL升级。
Bootloader 4.6 is the current bootloader being placed on iPhones as of Week 45 and later iPhones of 2007 and all 2008 iPhones. This bootloader does not allow your baseband to be downgraded, so once you updated, you are stuck there. Also, this bootloader does not allow the IPSF unlock. As you may remember this bootloader caused many problems when it was reviewed by the Dev-Team to look for a software unlock. Now, thanks to GeoHot, this bootloader [4.6] can be unlocked. One important exploit in this bootloader is that it can allow you to downgrade itself to the earlier 3.9 which is good if you want to downgrade baseband or apply IPSF-like unlock.
BL4。6是目前的BL用在45周和07年后的IP上和全部的08年IP。这个BL不允许降级BB，所以，当你升级后，你就卡在那了（降级不了了）。同时，这个BL不允许IPSF解锁（AnySim）。你可能还会记得这个BL给Dev-Team试图去软解锁的时候制造了很多麻烦。现在，感谢GeoHot，BL4。6可以解锁了。一个重要的开发是在这种BL里，它允许你降级BL自己到较早的BL3。9。这为降级BB和使用类似IPSF的方法解锁带来了方便。
Bootloader 3.9 Fakeblank (BL 3.9FB) is a modified bootloader created by Geohot and the Dev-Team. It has all the capabilites bootloader 3.9 has, but has one great exception. This bootloader, since it's modified, can allow you to updgrade back to bootloader 4.6. One big flaw of it, is that if you downgrade your firmware to 1.1.1 or earlier the bootloader seems to disappear and a new bootloader appears (more on that next).
BL3。9FB是一个改进后的BL，Geohot和Dev-Team编写了它。它拥有所有BL3。9支持的东西，但是有个很大的不同，这个BL，当它在设计的时候，允许你升级BL到4。6，一个大的问题是，当你降级固件到1.1.1过更早的时候，BL看起来好象消失了，而新的BL被写入了（下次会更多解释）
Bootloader 3.8 is very, very new. This bootloader is a mistake made by the iPhone when installing firmware 1.1.1 or earlier on a BL 3.9FB. Since, its new not many information is known, but here are some things. This bootloader occurs because 1.1.1 or earlier firmware thinks there is no bootloader (BL 3.9FB makes it look as though there is no actual bootloader). So the strongest suggestion is not to downgrade to 1.1.1 or earlier when using BL 3.9FB until the mistake is corrected. The greatest worry of this Bootloader is the fact it has all the exploits of 3.9, which means no bootloader upgrade. After this info, not much is really known of bootloader 3.8.
BL3。8是非常，非常的新。这个BL是个IP制造的错误当它在安装固件1.1.1或更早的在BL3.9FB上，目前，它还是很新的而且没有更多的了解，但是还是知道一些的。这个BL出现的原因是1.1.1或更早的固件没有检测到BL的存在（BL3。9FB让它看起来不像是个真正的BL）
所以强烈建议不要降级到1.1.1或更早的固件当你使用BL3.9FB知道这个问题被修复后，更大的担心关于这个BL是它是和3。9一样的，意思就是不允许升级BL。
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关键词：
Bootloader
中文：系统启动加载器
版本：
官方 3.9 4.6
自制 3.9_fake, 4.6_fake
主要功能，在开机进入系统之前，加载某些硬件初始化程序，启动系统进程。。诸如此类的东西，相当于PC的BIOS
