The USB standard, developed to unify several types of connections, has evolved and become popular, so that it has become a standard for connecting almost any type of gadget to the computer, in addition to serving as an interface between devices and their chargers.
The USB-C is becoming the most used version, however there are still a large number of devices that use old standards of USB technology, since the connection model in its vast majority is backwards compatible.
As the technology evolved, it gained new nomenclatures to indicate its version, such as USB 1.1, USB 2.0, USB 3.0, USB 3.1, USB 3.2 and USB 4. Even today, most of the simplest accessories, such as keyboards, mice and even cameras use the USB 2.0 standard, since, as it is an older technology, it offers reduced cost, even though it is capable of delivering the necessary performance for input devices. To better understand the difference between each one, we need to know their specifications:
USB 1.1: the beginning of universalization
Launched in the late 1990s, USB 1.1 was developed as its name suggests, to become a type of universal connection (Universal Serial Bus). It proved to be fundamental, since, years later, almost any external device to be connected to the PC would use the standard.
Initially, the promise was of communication speed that could operate between 1.5 and 12 Mbps, which shows its obsolescence for the present day, because, if it did not evolve, it would limit usability a lot.
USB 2.0: the established standard
The 2000s brought the USB 2.0 standard, which, as mentioned, is still used today in accessories that do not demand much transmission speed and energy. Because it is an inexpensive way to use technology, USB 2.0 is still very popular, especially in input devices.
In theory, USB 2.0 allows transfers of up to 480 Mbps, which is a notable gain over USB 1.1, but, as we will see below, it falls far short of the speeds offered by current standards.
USB 3.0: ideal for transfer speed
The USB 3 standard gained some revisions as the technology evolved, so that, until recently, it was suitable for devices that demand higher transfer speeds, such as external hard drives or SSDs. Nowadays it is still used in motherboards, consoles and others.
The USB added five pins to the connector, making a total of nine. If initially it promised transfers of up to 4.8 Gbps, its revision, USB 3.1, reaches speeds of up to 10 Gbps. It is worth mentioning that, even though it is possible to connect a USB 3 device to a USB 2 port, the transfer speed is limited by the port to be used.
USB 4.0: the arrival of USB-C
After several years, the USB changed, introducing the USB-C, which features the possibility of connecting the cable on both sides. Although USB-C does not fit directly into the previous standard, it can be used with adapters on older ports.
Arriving as an alternative to Thunderbolt 3, the USB-C reaches transfer speeds of up to 40 Gbps, in addition to being a very versatile connection, because in addition to performing high-speed data transfer, it allows the port to be used as an output high resolution video.