Hi, I'm Carrie Anne, and welcome to CrashCourse Computer Science!
(｡･∀･)ﾉﾞ嗨，我是 Carrie Anne \N 欢迎收看计算机科学速成课！

As we discussed last week, the idea of having a computer all to yourself a personal
上周说过"个人计算机"的概念 \N 在计算机发展的头 30 年难以想象

computer was elusive for the first three decades of electronic computing.
上周说过"个人计算机"的概念 \N 在计算机发展的头 30 年难以想象

It was just way too expensive for a computer to be owned and used by one single person.
如果只让一个人用，成本实在太高

But, by the early 1970s, all the required components had fallen into place to build
但到 70 年代初，各种组件的成本都下降了 \N 可以做出低成本  同时性能足够强大的计算机

a low cost, but still usefully powerful computer.
但到 70 年代初，各种组件的成本都下降了 \N 可以做出低成本  同时性能足够强大的计算机

Not a toy, but a tool.
不是玩具级计算机，是真正能用的计算机

Most influential in this transition was the advent of single-chip CPUs,
这个转变中 \N 最有影响力的是 单芯片 CPU 的出现

which were surprisingly powerful, yet small and inexpensive.
强大 + 体积小 + 便宜

Advances in integrated circuits also offered low-cost solid-state memory,
集成电路的进步，也提供了低成本固态存储器

both for computer RAM and ROM.
可以用于计算机的 RAM 和 ROM

Suddenly it was possible to have an entire computer on one circuit board,
忽然间 \N 把整台计算机做到一张电路板上成为可能

dramatically reducing manufacturing costs.
大大地降低了制造成本

Additionally, there was cheap and reliable computer storage,
而且，那时有便宜可靠的储存介质 \N 比如磁带和软盘

like magnetic tape cassettes and floppy disks.
而且，那时有便宜可靠的储存介质 \N 比如磁带和软盘

And finally, the last ingredient was low cost displays, often just repurposed televisions.
最后是 低成本的显示器 \N 通常是电视机稍作改装而成

If you blended these four ingredients together in the 1970s, you got,
如果在 1970 年代 \N 将这四种原料混在一起

what was called a microcomputer,
就得到了"微型计算机"

because these things were so tiny compared to "normal" computers of that era, the
因为和那个时代的"普通"计算机相比 \N 这些计算机很小

types you'd see in business or universities.
"普通"计算机就是公司或大学里的那种

But more important than their size was their cost.
但比大小更重要的是成本

These were, for the first time, sufficiently cheap.
这是有史以来第一次，计算机的价格足够低

It was practical to buy one and only have one person ever use it.
"一个人专用"的想法变得可行

No time sharing,
不用划分时间和别人公用计算机

no multi-user logins,  just a single owner and user.
没有多用户登录，计算机只属于一个人，只有一个用户

The personal computer era had arrived.
个人计算机时代到来

Computer cost and performance eventually reached the point
计算机成本下降+性能提升, 让个人计算机成为可能

where personal computing became viable.
计算机成本下降+性能提升, 让个人计算机成为可能

But, it's hard to define exactly when that happened.
但这个时间点很难准确定义, 并没有一个具体时间点

There's no one point in time.
但这个时间点很难准确定义, 并没有一个具体时间点

And as such, there are many contenders for the title of "first" personal computer,
因此"第一台个人计算机"这个名号，有很多竞争者

like the Kenback-1 and MCM/70.
比如 Kenback-1 和 MCM/70

Less disputed, however, is the first commercially successful personal computer: The Altair 8800.
不过第一台取得商业成功的个人计算机 \N 争议较小：Altair 8800

This machine debuted on the cover of Popular Electronics in 1975,
首次亮相在 1975 年《Popular Electronics》封面

and was sold as a $439 kit that you built yourself.
售价 $439 美元，需要自己组装

Inflation adjusted, that's about $2,000 today,
计算通货膨胀后，相当如今的 2000 美元左右

which isn't chump change, but extremely cheap for a computer in 1975.
不算小钱，但比起 1975 年的其它计算机，算是非常便宜了

Tens of thousands of kits were sold to computer hobbyists,
各种需要自己组装的组件包  \N卖给了计算机爱好者

and because of its popularity, there were soon all sorts of nifty add-ons available...
因为买的人多，很快相关产品出现了

things like extra memory, a paper tape reader and even a teletype interface.
比如内存，纸带读取器，甚至电传接口

This allowed you, for example, to load a longer, more complicated program from punch tape,
让你可以从纸带上读取更长更复杂的程序

and then interact with it using a teletype terminal.
然后用电传终端交互

However, these programs still had to be written in machine code,
但程序还是要用 机器码 写

which was really low level and nasty, even for hardcore computer enthusiasts.
写起来很麻烦，即使计算机爱好者也讨厌写

This problem didn't escape a young Bill Gates and Paul Allen,
这没有吓跑年轻的比尔·盖茨和保罗·艾伦

who were 19 and 22 respectively.
他们当时是19岁和22岁

They contacted MITS, the company making the Altair 8800,
他们联系了制造 Altair 8800 的 MITS 公司

suggesting the computer would be more attractive to hobbyists
建议说，如果能运行 BASIC 程序 \N 会对爱好者更有吸引力

if it could run programs written in BASIC,
建议说，如果能运行 BASIC 程序 \N 会对爱好者更有吸引力

a popular and simple programming language.
BASIC 是一门更受欢迎更简单的编程语言

To do this, they needed to write a program that converted BASIC instructions
为此，他们需要一个程序 \N 把 BASIC 代码转成可执行机器码

into native machine code, what's called an interpreter.
这叫 解释器 (interpreter)

This is very similar to a compiler,
"解释器"和"编译器"类似

but happens as the programs runs instead of beforehand.
区别是"解释器"运行时转换\N而"编译器"提前转换

Let's go to the thought bubble!
让我们进入思想泡泡！

MITS was interested,
MITS 表示感兴趣

and agreed to meet Bill and Paul for a demonstration.
同意与 Bill 和 Paul 见个面，让他们演示一下

Problem is, they hadn't written the interpreter yet.
问题是，他们还没写好解释器

So, they hacked it together in just a few weeks
所以他们花了几个星期赶工 \N 而且还不是在 Altair 8800 上写的

without even an Altair 8800 to develop on,
所以他们花了几个星期赶工 \N 而且还不是在 Altair 8800 上写的

finishing the final piece of code on the plane.
最后在飞机上完成了代码

The first time they knew their code worked was at MITS headquarters
他们在墨西哥 阿尔伯克基（城市） \N 的 MITS 总部做演示时，才知道代码可以成功运行

in Albuquerque, New Mexico, for the demo.
他们在墨西哥 阿尔伯克基（城市） \N 的 MITS 总部做演示时，才知道代码可以成功运行

Fortunately, it went well and MITS agreed to distribute their software.
幸运的是进展顺利 \N MITS 同意在计算机上搭载他们的软件

Altair BASIC became the newly formed Microsoft's first product.
Altair BASIC 成了微软的第一个产品

Although computer hobbyists existed prior to 1975,
虽然1975年之前就有计算机爱好者

the Altair 8800 really jump-started the movement.
但 Altair 8800 大量催生了更多计算机爱好者

Enthusiast groups formed, sharing knowledge and software and passion about computing.
爱好者们组成各种小组 \N 分享知识，软件，以及对计算机的热爱

Most legendary among these is the Homebrew Computer Club,
最具传奇色彩的小组是"家酿计算机俱乐部"

which met for the first time in March 1975
第一次小组聚会在1975年3月

to see a review unit of the Altair 8800, one of the first to ship to California.
看一台第一批运来加州的 Altair 8800

At that first meeting was 24-year-old Steve Wozniak, who was so inspired by
第一次聚会上，24岁的 Steve Wozniak  \N 被 Altair 8800 大大激励

the Altair 8800 that he set out to design his own computer.
开始想设计自己的计算机

In May 1976, he demonstrated his prototype to the Club
1976年5月，他向小组展示了原型机

and shared the schematics with interested members.
并且把电路图分享给感兴趣的其他会员

Unusual for the time, it was designed to connect to a TV and offered a text interface
他的设计不同寻常 \N 要连到电视显示，并提供文本界面

a first for a low-cost computer.
在低成本计算机上还是第一次见

Interest was high, and shortly after fellow club member and college friend Steve Jobs
同是俱乐部成员和大学朋友的 史蒂夫·乔布斯

suggested that instead of just sharing the designs for free,
建议说与其免费分享设计，不如直接出售装好的主板

they should just sell an assembled motherboard.
建议说与其免费分享设计，不如直接出售装好的主板

However, you still had to add your own keyboard, power supply, and enclosure.
但用户依然需要自己加键盘，电源和机箱

It went on sale in July 1976 with a price tag of $666.66.
1976年7月开始发售，价格$666.66美元

It was called the Apple-I, and it was Apple Computer's first product.
它叫 Apple-I ，苹果计算机公司的第一个产品

Thanks thought bubble!
谢了 思想泡泡

Like the Altair 8800, the Apple-I was sold as a kit.
就像 Altair 8800 一样，Apple-I 也是作为套件出售

It appealed to hobbyists,
Apple-I 吸引了业余爱好者 \N 不介意机器买回来自己组装

who didn't mind tinkering and soldering,
Apple-I 吸引了业余爱好者 \N 不介意机器买回来自己组装

but consumers and businesses weren't interested.
但个人消费者和公司对 Apple-I 不感兴趣

This changed in 1977,
这在 1977 年发生变化 \N 市场上有了三款开箱即用的计算机

with the release of three game-changing computers,  that could be used right out of the box.
这在 1977 年发生变化 \N 市场上有了三款开箱即用的计算机

First was the Apple II,
第一款是 Apple-II

Apple's earliest product that sold as a complete system
苹果公司第一个提供全套设备的产品

that was professionally designed and manufactured.
设计和制造工艺都是专业的

It also offered rudimentary color graphics and sound output,
它还提供了简单彩色图形和声音输出

amazing features for a low cost machine.
这些功能对低成本机器非常了不起

The Apple II series of computers sold by the millions and quickly
Apple-II 卖了上百万套

propelled Apple to the forefront of the personal computing industry.
把苹果公司推到了个人计算机行业的前沿

The second computer was the TRS-80 Model I,
第二款是"TRS-80 1型"

made by the Tandy Corporation
由 Tandy 公司生产

and sold by RadioShack hence the "TRS"
由 Radioshack 销售，所以叫 TRS

Although less advanced than the Apple II,
虽然不如 Apple-II 先进 \N 但因为价格只有一半，所以卖得很火爆

it was half the cost and sold like hot cakes.
虽然不如 Apple-II 先进 \N 但因为价格只有一半，所以卖得很火爆

Finally, there was the Commodore PET 2001,
最后一款是 Commodore PET 2001

with a unique all-in-one design
有一体化设计

that combined computer, monitor, keyboard and tape drive into one device,
集成了计算机，显示器，键盘和磁带驱动器

aimed to appeal to consumers.
目标是吸引普通消费者

It started to blur the line between computer and appliance.
计算机和家用电器之间的界限开始变得模糊

These three computers became known as the 1977 Trinity.
这3台计算机被称为1977年的"三位一体"

They all came bundled with BASIC interpreters,
它们都自带了 BASIC 解释器

allowing non-computer-wizards to create programs.
让不那么精通计算机的人也能用 BASIC 写程序

The consumer software industry also took off,
针对消费者的软件行业 开始腾飞

offering games and productivity tools for personal computers,
市场上出现了各种 \N 针对个人计算机的游戏和生产力工具

like calculators and word processors.
比如计算器和文字处理器

The killer app of the era was 1979's VisiCalc,
最火的是 1979 年的 VisiCalc

the first spreadsheet program
第一个电子表格程序

which was infinitely better than paper
比纸好无数倍

and the forbearer of programs like Microsoft Excel and Google Sheets.
是微软 Excel 和 Google Sheets 的老祖先

But perhaps the biggest legacy of these computers was their marketing,
但这些计算机带来的最大影响 \N 也许是他们的营销策略

they were the first to be targeted at households, and not just businesses and hobbyists.
它们针对普通消费者 \N 而不是企业和爱好者

And for the first time in a substantial way,
这是第一次大规模地

computers started to appear in homes, and also small businesses and schools.
计算机出现在家庭，小公司，以及学校中

This caught the attention of the biggest computer company on the planet, IBM, who had seen its
这引起了全球最大计算机公司 IBM 的注意

share of the overall computer market shrink from 60% in 1970 to around 30% by 1980.
其市场份额从1970年的60％ \N 在1980年降到了30％左右

This was mainly because IBM had ignored the microcomputer market,
因为IBM忽略了增长的"微型计算机"市场

which was growing at about 40% annually.
这个市场每年增长约40％

As microcomputers evolved into personal computers, IBM knew it needed to get in on the action.
随着微型计算机演变成个人计算机 \N IBM 知道他们需要采取行动

But to do this, it would have to radically rethink its computer strategy and design.
但要做到这一点 \N 公司要从根本上重新思考战略和设计

In 1980, IBM's least-expensive computer, the 5120, cost roughly ten thousand dollars,
1980年 IBM 最便宜的计算机 \N "5120"的价格大概是一万美元

which was never going to compete with the likes of the Apple II.
永远也没法和 Apple-II 这样的计算机竞争

This meant starting from scratch.
意味着要从头开始

A crack team of twelve engineers, later nicknamed the dirty dozen,
一个由十二名工程师组成的精干团队（后来叫"肮脏十二人"）

were sent off to offices in Boca Raton, Florida,
被派往佛罗里达州的 \N 博卡拉顿（Boca Raton）办公室

to be left alone and put their talents to work.
让他们独立工作

Shielded from IBM internal politics, they were able to design a machine as they desired.
不受 IBM 内部的政治斗争干扰 \N 他们想怎么设计怎么设计

Instead of using IBM proprietary CPUs, they chose Intel chips.
没用 IBM 的 CPU，选了 Intel 的芯片

Instead of using IBM's prefered operating system, CP/M,
也没用 IBM 的首选操作系统 CP/M

they licenced Microsoft's Disk Operating System: DOS
而是用了微软的 DOS

and so on, from the screen to the printer.
依此类推，从屏幕到打印机都这样自由选择

For the first time, IBM divisions had to compete with outside firms
IBM 第一次不得不与外部公司竞争

to build hardware and software for the new computer.
来给新计算机做硬件和软件

This radical break from the company tradition of in-house development kept costs low
这和 IBM 的传统做法不同：自己做硬件来节省成本

and brought partner firms into the fold.
然后和其它公司合作

After just a year of development,
经过短短一年

the IBM Personal Computer, or IBM PC was released.
IBM 个人计算机发布了，简称 IBM PC

It was an immediate success,
产品立马取得了成功

especially with businesses that had long trusted the IBM brand.
长期信任 IBM 品牌的企业买了很多

But, most influential to its ultimate success was that the computer featured an open architecture,
但最有影响力的是 \N 它使用 "开放式架构"

with good documentation and expansion slots,
有良好的文档和扩展槽

allowing third parties to create new hardware and peripherals for the platform.
使得第三方可以做硬件/外设

That included things like graphics cards, sounds cards, external hard drives, joysticks,
包括显卡，声卡，外置硬盘，游戏控制杆 \N 以及无数其它组件

and countless other add-ons.
包括显卡，声卡，外置硬盘，游戏控制杆 \N 以及无数其它组件

This spurred innovation, and also competition, resulting in a huge ecosystem of products.
这刺激了创新，激发了竞争，产生了巨大的生态系统

This open architecture became known as "IBM Compatible".
这个开放架构叫 IBM Compatible"（IBM 兼容）

If you bought an "IBM Compatible" computer, it meant you
意味着如果买了"IBM兼容"的计算机

could use that huge ecosystem of software and hardware.
你可以用庞大生态系统中的其它软硬件

Being an open architecture also meant that competitor companies could follow the standard
开放架构也意味着 竞争对手公司可以遵循这个标准

and create their own IBM Compatible computers.
做出自己的"IBM 兼容"计算机

Soon, Compaq and Dell were selling their own PC clones...
很快，康柏和戴尔也开始卖 PC

And Microsoft was happy to license MS-DOS to them,
微软很乐意把 MS-DOS 授权给他们

quickly making it the most popular PC operating system.
使 DOS 迅速成为最受欢迎的 PC 操作系统

IBM alone sold two million PCs in the first three years, overtaking Apple.
仅在前三年 \N IBM就卖出了200万台 PC ，超过了苹果

With a large user base, software and hardware developers concentrated
有了庞大用户群，软件和硬件开发人员 \N 把精力放在"IBM 兼容"平台，因为潜在用户更多

their efforts on IBM Compatible platforms, there were just more users to sell to.
有了庞大用户群，软件和硬件开发人员 \N 把精力放在"IBM 兼容"平台，因为潜在用户更多

Then, people wishing to buy a computer bought the one with the
同时，想买计算机的人 \N 也会看哪种计算机的软硬件选择更多

most software and hardware available, and this effect snowballed.
就像雪球效应一样

Companies producing non-IBM-compatible computers, often with superior specs,
而那些生产非"IBM兼容"计算机的公司 （一般性能更好）

failed.
都失败了

Only Apple kept significant market share without IBM compatibility.
只有苹果公司在没有"IBM兼容"的情况下 \N 保持了足够市场份额

Apple ultimately chose to take the opposite approach a "closed architecture" proprietary
苹果公司最终选了相反的方式："封闭架构"

designs that typically prevent people from adding new hardware to their computers.
即自己设计一切，用户一般无法加新硬件到计算机中

This meant that Apple made its own computers, with its own operating system, and often its
意味着苹果公司要做自己的计算机，自己的操作系统

own peripherals, like displays, keyboards, and printers.
还有自己的外围设备，如显示器，键盘和打印机

By controlling the full stack, from hardware to software,
通过控制整个范围，从硬件到软件

Apple was able to control the user experience and improve reliability.
苹果能控制用户体验并提高可靠性

These competing business strategies were the genesis of the "Mac" versus "PC" division
不同的商业策略是"Mac vs PC 谁更好"这种争论的起源

that still exists today... which is a misnomer, because they're both personal computers!
这些争论如今还存在 \N 不过"Mac vs PC"用词不对，因为它们都是个人计算机！

But whatever.
但是随便啦

To survive the onslaught of low-cost PCs,
为了在低成本个人计算机的竞争冲击下生存下来

Apple needed to up its game,
苹果需要提高自身水平 \N 提供比 PC 和 DOS 更好的用户体验

and offer a user experience that PCs and DOS couldn't.
苹果需要提高自身水平 \N 提供比 PC 和 DOS 更好的用户体验

Their answer was the Macintosh, released in 1984.
他们的答案是 Macintosh，于 1984 年发布

This ground breaking, reasonably-low-cost, all-in-one computer
一台突破性 价格适中的一体式计算机 \N 用的不是命令行界面，而是图形界面

booted not a command-line text-interface, but rather a graphical user interface,
一台突破性 价格适中的一体式计算机 \N 用的不是命令行界面，而是图形界面

our topic for next week. See you then.
我们下周讨论图形界面. 到时见

