USB 技术^{(USB technology)}已经存在了20 多年。我们已经习惯了它，以至于我们认为它是理所当然的，我们并不认为它特别。尽管几乎不可能从未使用过USB 设备^{(USB device)}或将USB 连接器^{(USB connector)}插入USB 端口^{(USB port)}，但您可能并不真正了解USB的含义以及这项技术的作用。您可能听说过USB Type C之类的首字母缩略词，但仅此而已。在这篇文章中，我们将解释USB是什么，给你一些关于这个标准的历史，并分享^{(standard and share)}不同类型的端口之间的差异，比如USB Type C，微型 USB^{(Micro USB)}、USB 3.0等。让我们开始吧：

USB 代表什么？

USB代表通用串行总线^{(Universal Serial Bus)}，它代表了电缆、连接器和通信协议的行业标准^{(industry standard)}，用于各种计算设备之间的连接、通信和供电。^{(power supply)}它被各种各样的设备使用，从普通的键盘和鼠标^{(keyboard and mouse)}到相机、打印机、扫描仪、闪存驱动器、外部硬盘驱动器、智能手机、平板电脑、电视^(TVs)等。

通用串行总线^{(Universal Serial Bus)}是即插即用接口，这意味着您可以将具有 USB 端口的设备连接到^{(USB port)}您的计算机，计算机将能够自动检测并安装该设备，尽管有时您必须提供操作系统^{(operating system)}所需的驱动程序。为了充当一种通信方式，USB可以在它所连接的设备之间传输数据，例如从您的计算机到您的键盘，反之亦然。

USB还可以为设备供电。此功能是其最有用的特性之一，因为它不仅可以让您的设备在它们之间进行通信，还可以让您为设备供电或为设备中的电池充电。例如，我们今天使用的大多数外部硬盘驱动器都是通过它们的USB 端口^{(USB port)}单独供电，而不使用单独的电源适配器。此外，智能手机有一个USB 端口^{(USB port)}，可用于数据传输和电池充电。

USB 标准^{(USB standard)}的简史

通用串行总线^{(Universal Serial Bus)}，简称USB，于 1996 年由几家主要公司设计：康柏^(Compaq)、DEC、IBM、英特尔^(Intel)、微软^(Microsoft)、NEC和北电^(Nortel)。

在USB发明之前，计算机过去常常通过使用各种类型的端口和连接来连接到键盘、鼠标、打印机、扫描仪、相机等外围设备。例如，在采用USB之前，键盘和鼠标通常通过PS/2连接器或串行端口连接。打印机和扫描仪通常通过并行端口连接。如果您当时是一名游戏玩家，如果您想使用操纵杆或游戏手柄在计算机上玩游戏，您还需要一个游戏端口。^{(game port)}只需^(Just)看一下下图中的示例：

最初的USB 端口^{(USB port)}不具备高速传输的能力，硬件制造商从一开始就没有接受这个接口。但是，在它首次开发几年后，USB 接口^{(USB interface)}被创建它的公司修改，他们制作了USB 2.0 版本^{(USB version 2.0)}，速度快了很多。正因为如此，在2000 年^{(year 2000)}之后，USB 端口^{(USB port)}出现了大规模扩展，现在在各种设备上都可以找到它。从那时起，USB就成为连接设备和在设备之间传输数据的主要方式。

USB版本和数据传输速度

自首次开发以来，USB 接口^{(USB interface)}在每次修订后都在不断加快速度。以下是 USB 的主要修订或版本：

1. USB 1.0和USB 1.1 - 是 USB 接口的第一次迭代，分别于 1996 年和 1998 年发布，它们的数据传输速度分别高达 1.5 Mbps 和 12 Mbps。在开发它们的时候，USB 1.0也被称为Low Speed USB，而USB 1.1被称为Fast Speed USB。

2. USB 2.0 - 也称为高速 USB^{(Hi-Speed USB)}，于 2000 年 4 月发布，它支持高达 480 Mbps 的最大理论数据传输速度。实际上，最大有效吞吐量限制为 280 Mbps 或 35 MB/s。USB 2.0向后兼容USB 1.0和USB 1.1，这意味着您可以使用带有USB 1.x端口的旧设备连接到带有USB 2.0端口的新设备。

3. USB 3.0 - 于 2008 年 11 月问世，也称为SuperSpeed USB。它可以支持高达 5 Gbps 的理论数据传输速度，但您可以获得的实际速度约为 3.2 Gbps 或 400 MB/s。

4. USB 3.1 - 于 2013 年 7 月发布，也称为SuperSpeed+ USB。它能够进行 10 Gbps 的理论数据传输，是USB 3.0的两倍。实际上，可实现的最大传输速度为 7.2 Gbps 或 900 MB/s。

如何区分USB 3.x端口和USB 2.0端口？

为了区分USB 3.x端口与USB 2.0或USB 1.x端口，USB 3.x端口通常为蓝色。以前的USB版本- USB 2.0和USB 1.x - 通常被涂成黑色。

资料来源：^(Source:)维基百科^(Wikipedia)

USB 连接器和端口的类型

USB 端口^{(USB port)}和连接器^{(s and connectors)}有很多种类型，在我们向您展示最常见的类型之前，让我们先看看USB 端口^{(USB port)}和USB 连接器^{(USB connector)}有什么区别：

• USB连接器^{(USB connector)}是连接到USB 端口的^{(USB port)}USB 电缆^{(USB cable)}的末端。
• USB端口^{(USB port)}是计算机或设备^{(computer or device)}上插入USB 连接器^{(USB connector)}的位置。

以下是最常见的USB连接器：

• USB A 型^{(USB Type A)}- 是最常见的 USB 连接器和端口类型。这种类型的端口可能在大多数计算机和笔记本电脑上都可以找到。连接器又大又笨重，位于将插入计算机的 USB 电缆的末端。当第一个 USB 规范于 1996 年发布时，这种USB Type A与^{(USB Type A)}USB Type B一起出现。

• USB B 型^{(USB Type B)}- 可能是目前最大的 USB 连接器，USB B 型^{(USB Type B)}是方形的，两个角上有两个小斜面。USB B 型^{(USB Type B)}连接器通常用于插入打印机、扫描仪和其他大型设备的 USB 电缆的末端。

• Mini USB - 是^{(Mini USB)}USB A 型^{(USB Type A)}和USB B 型^{(USB Type B)}连接器的较小版本。它们于 2000 年推出。然而，如今Mini USB连接器非常罕见，因为它们已被较新的^{(Mini USB)}Micro USB连接器过时。

• Micro USB - 比Mini USB连接器更小，是当今使用最广泛的 USB 连接器，尤其是在智能手机和相机上。它们于 2007 年推出。

• USB Type C - 是 USB 连接器的最新版本，于 2014 年发布，它具有三个特点：体积小、可逆、通常用于USB 3.1端口。USB Type C连接器大约是在USB 3.1发布的同时创建的，因此人们普遍错误地认为USB 3.1和USB Type C是一回事。实际上，它们不是，因为USB 3.1是一种 USB 协议，而USB Type C是一种连接器规范。虽然不是很常见，但有些设备可以使用USB Type C连接器，但仅支持 USB 2.0。考虑到所有因素，未来都是关于USB 3.1和USB Type C的，因此您应该期待市场上推出更多兼容设备。

资料来源：^(Source:)维基百科^(Wikipedia)

结论

现在您对USB^(USB)代表什么以及它为何有用有了更清晰的认识。此外，您还知道该标准是如何随着时间的推移而演变的，以及多种类型的USB连接器之间的差异。如果您对此主题有任何疑问，请随时使用下面的评论表提问。

Simple questions: What is USB (Universal Serial Bus)?

The USB technology has been around for more thаn 20 years nоw. We'νe become so used to it that we take it for granted and we don't consider it special. Although it's almost impossible to have never used a USB device or to havе plugged a USB conneсtor into a USB port, it possible that you don't really know what USB means, and what this technology does. You mіght have heard some acronyms like USB Type C but that's pretty much it. In this article, we will explain what USB is, give you a bit of history about this standard and share the differences between the different types of ports like USB Type C, Micro USB, USB 3.0 and so on. Let's get started:

What does USB stand for?

USB stands for Universal Serial Bus, and it represents an industry standard for cables, connectors and communications protocols, used for the connection, communication, and power supply between various computing devices. It is used by a very large variety of devices, ranging from the common keyboard and mouse to cameras, printers, scanners, flash drives, external hard drives, smartphones, tablets, TVs and so on.

The Universal Serial Bus is a plug-and-play interface, meaning that you can connect a device that has a USB port to your computer, and the computer will be able to automatically detect and install the device, although sometimes you will have to provide the necessary drivers for your operating system. In order to act as a means of communication, USB can transfer data to and from the devices it connects, like from your computer to your keyboard and the other way around.

USB can also supply power to devices. This feature is one of its most useful traits because it allows you not only to make your devices communicate between them, but it also lets you power them or charges the batteries in your devices. For instance, most of the external hard drives we use today, are powered exclusively via their USB ports, without using separate power adapters. Also, smartphones have a USB port that's used both for data transfers and for charging their batteries.

A very brief history of the USB standard

The Universal Serial Bus, or USB in short, was designed in 1996, by several key companies: Compaq, DEC, IBM, Intel, Microsoft, NEC, and Nortel.

Before USB was invented, computers used to connect to peripherals like keyboards, mice, printers, scanners, cameras and so on, by using various types of ports and connections. For instance, before USB was adopted, keyboards and mice usually connected via PS/2 connectors or by using serial ports. Printers and scanners usually connected via parallel ports. And if you were a gamer back in those days, you also needed a game port if you wanted to play games on your computer using a joystick or a gamepad. Just take a look at the examples from the picture below:

The first USB ports were not capable of high-speed transfers, and hardware manufacturers did not embrace this interface right from the start. But, a few years after it was first developed, the USB interface was revised by the companies that created it, and they made USB version 2.0, which was a lot faster. Because of that, after the year 2000, the USB port saw a massive expansion and it is now found on all kinds of devices. Since then, USB has become the main way of connecting devices and transferring data between them.

USB versions and data transfer speeds

Since it was first developed, the USB interface kept on getting faster with each revision. Here are the main revisions or versions of USB:

1. USB 1.0 and USB 1.1- were the first iterations of the USB interface, released in 1996 and 1998 respectively, and they were capable of data transfers of up to 1.5 Mbps, respectively 12 Mbps. At the time when they were developed, USB 1.0 was also known as Low Speed USB, while the USB 1.1 was known as Fast Speed USB.

2. USB 2.0 - also known as Hi-Speed USB, was released in April 2000 and it supports maximum theoretical data transfer speeds of up to 480 Mbps. In reality, the maximum effective throughput is limited to 280 Mbps or 35 MB/s. USB 2.0 is backward compatible with USB 1.0 and USB 1.1, meaning that you can use old devices with USB 1.x ports to connect to newer devices that have USB 2.0 ports.

3. USB 3.0 - came to life in November 2008 and it is also known as SuperSpeed USB. It can support theoretical data transfer speeds of up to 5 Gbps, but the real-life speeds you can get on it are around 3.2 Gbps or 400 MB/s.

4. USB 3.1 - was released in July 2013 and is also known as SuperSpeed+ USB. It is capable of theoretical data transfers of 10 Gbps, double that of USB 3.0. In reality, the maximum achievable transfer speed is of 7.2 Gbps or 900 MB/s.

How do I differentiate between USB 3.x ports and USB 2.0 ports?

To differentiate USB 3.x ports from USB 2.0or USB 1.x ports, the USB 3.x ports are usually colored blue. The previous versions of USB - USB 2.0and USB 1.x - were usually painted black.

Source:Wikipedia

Types of USB connectors and ports

There are many types of USB ports and connectors, and before we show you the most common, let's see first what's the difference between a USB port and a USB connector:

• A USB connector is the end of a USB cable that connects to a USB port.
• A USB port is a location on your computer or device into which you plug a USB connector.

Here are the most common USB connectors:

• USB Type A - is the most common type of USB connector and port. This type of port is probably found on the majority of computers and laptops. The connector is large and bulky, found at the end of the USB cable that you will plug into your computer. This USB Type A appeared together with USB Type B, when the first USB specification was released, in 1996.

• USB Type B - probably the largest USB connector out there, the USB Type B is square shaped, with two small bevels on two of its corners. The USB Type B connector is generally used at the end of the USB cable that plugs into your printer, scanner, and other large devices.

• Mini USB - are smaller versions of the USB Type Aand USB Type B connectors. They were introduced in 2000. However, Mini USB connectors are very rare these days, as they became outdated by the newer Micro USB connectors.

• Micro USB - are even smaller than Mini USB connectors and are the most widely used USB connectors today, especially on smartphones and cameras. They were introduced in 2007.

• USB Type C - is the newest version of a USB connector, released in 2014, and it's characterized by three things: it's small, it's reversible, and it's generally used for USB 3.1 ports. The USB Type C connector was created roughly at the same time when the USB 3.1 was released, hence the common mistake people make to assume that USB 3.1 and USB Type C are one and the same. In reality, they're not, as USB 3.1 is a USB protocol, while the USB Type C is a connector specification. Although it's not very common, some devices can use USB Type C connectors but only support USB 2.0. All things considered, the future is all about USB 3.1 and USB Type C, so you should expect more compatible devices being launched on the market.

Source:Wikipedia

Conclusion

Now you have a clearer idea of what USB stands for and why it's useful. Also, you know how this standard has evolved over time and the differences between the many types of USB connectors. If you have any questions about this subject, don't hesitate to ask using the comments form below.

Related posts

• 如何使用USB cable在Windows 10计算机上添加本地打印机

• 如何在 USB 驱动器上安装 Windows 11 和 Windows 10 (Windows To Go)

• 在 Windows 中格式化 SD 卡、USB 记忆棒或硬盘分区的 2 种方法

• 从 USB 闪存驱动器启动 Windows 10 PC 的 3 种方法 -

• 如何使用Windows Memory Diagnostic tool测试您的RAM

• 如何更改 Windows 10 中的默认声音设备（播放和录音）

• 从Windows 10弹出外部硬drive or USB的5种方法

• 将外接显示器连接到装有 Windows 10 的笔记本电脑的 3 种方法

• Fix problem：Drag and drop不在Windows工作

• 系统要求：我的电脑可以运行Windows 11吗？

• 在 Windows 10 中重命名任何驱动器的 5 种方法

• 如何从Windows卸载驱动程序，以5步

• 哪里可以找到Windows 10 refresh rate？如何改变它？

• 华硕 FX 硬盘评测：具有 RGB 和 AURA Sync 的便携式硬盘！

• 如何在 Mac OS X 中安装 Windows 7 或 8 网络共享打印机

• 我的Windows 10 PC，笔记本电脑或平板电脑是什么型号？ 8种方法可以找到

• Windows 设备管理器可以做的 7 件事

• 在 Windows 中删除分区的两种方法，无需第三方应用程序

• 在 Windows 中使用磁盘管理工具可以做的 7 件事

• 什么是司机？司机做了什么？