Cables may not be sexy but they are a necessary part of connecting your music system so that you can listen to your favourite tunes. They are not popular things in the wireless communication age but when it comes to turntables and decent sound systems they are a necessary evil. If some of the signal is lost from one component to another there's nothing that can be done to bring it back. Cables are almost as important as the components they keep connected. Cables can lose information and they can distort it, so the cable that makes the smallest changes to the signal is the best one.
Some turntable cables are fixed and cannot be changed ,but many have RCA sockets which means that you can upgrade the cables. If you have a nice turntable it is doing it a disservice to use cheap cables.
Interconnects are the cables that take the signal from a source such as a turntable, streamer or CD player to the amplifier. There are digital and analogue interconnects with both having the same RCA phono connector, but you only need one cable for a digital signal. Digital can be sent electrically via a coaxial cable or optically with a toslink cable. The other digital option is USB and there are some turntables that have a USB output so that you can record your vinyl onto your computer. Digital cables can vary in their sound as well.
Speaker cables are the final link in the chain and they can also make a difference to sound quality. If you want deep bass or high volumes you should avoid really skinny cables.
The materials from which cables are made vary and whilst most use copper as a signal conductor, there are different grades of copper, and some high end cables use silver as it is a marginally better conductor. A good compromise is silver plated copper which is used in a lot of higher end cables.
Upgrading your cables will result in a more realistic and engaging musical experience.The cable is usually the weakest link and anything that is done to improve results in a significantly different listening experience. A better cable makes the music more immediate, lifelike and present in the room.