What are the differences between CAT5 and other categories of twisted pair cables ?

CAT3 can be relied on to handle data speeds of up to10 Mbps, but no more. Its maximum frequency clocks in at16 MHz. Like many other cabling options, it relies on copper for data and power transmission. While theoretically limited to10BASE-T Ethernet, it can actually support100BASE-T4 speeds by using4 wires instead of2 to achieve100 Mbps throughput. And similar is CAT5.

whereas, CAT5 uses either the10BASE-T or100BASE-T standard for data transmission. Using two cable pairs to signal over copper wire, CAT5 is now largely archaic and isn’t widely used for Ethernet connections. It’s rated for a maximum frequency of100 MHz and top speeds of100 Mbps. CAT5 uses8P8C modular connectors to connect devices together, and can be used effectively at lengths of up to100 meters. Today, CAT5 cable has been replaced for the most part by CAT5e.

The major difference between the CAT's Categories How long CAT4, CAT5, CAT6 transmit the data without losing and little bit difference in thickness but it doesn't matter; Main thing is how long transmit data.

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Specifications for Cat3, Cat4, Cat5, Cat5e, Cat6, and Cat7

CAT5 refers to Category5 cable.  the dfiference between these is based on the thickness of wire and the longer range to transmit data they can provide. beginning with cat4 with smallest thickness.

followed by cat5 and cat6