The different cables that we use for data transmission are categorized into 7 different categories
. You may want to quickly review what each category entails so you don't get the cables mixed up. They all look similar but cannot all be used for the same purposes.
The category 1 cables are sometimes mistaken as real cables when they really aren't. They aren't used anymore but when they were they were used for simple things like doorbells. Some people know them by the name voice-grade copper.
A category 2 cable or cat 2 cable isn't used anymore either. It was used for transmitting information with the speed of 4 Mbit/sec. It is similar to the cat 1 cables in that it's not really seen as a true cable.
Category 3 cables are where they start to really classify them as recognized cables. Cat 3 has a maximum bandwidth of 16 MHz with up to 10 Mbit/sec for carrying data. Cat 3 was known for its use in computer networks about 20 years ago. The invention of the cat 5 cable has slowly weeded cat 3 cables out.
The cat-4 cable isn't very well known. It's used for transmitting information across token ring networks. Its bandwidth is 20 MHz and its speed is 16 Mbit/s. These were easily replaced with the well-known cat-5 cables.
The well-known category 5 cabling came into use over a decade ago. People also call these cables Ethernet cables that are plugged into Ethernet ports. These Ethernet ports require RJ-45 cable ends which are normally found on the category 5 cables. If there is a different jack end on the cables, the Ethernet port won't be able to take it.
There are some cat 6 and cat 7 cables that have an even greater bandwidth and speed. These are also used for Ethernet purposes and can be used in place of a cat 5 cable. The cat 6 and cat 7 cables are also better insulated which really improve the interference through the lines.
Understanding all the different kinds of cables really isn't too important. As long as you know which cables can be interchanged you will be set. The most common cable is the cat 5 cable as most people use it for their Internet connections.