Cables: What's the Difference & What Do I Need?
These days, it would seem like there is an infinite variety of cables, adaptors and connections for all types of situations and applications. If you're not familiar with the different cable types and their specific uses, knowing what you actually need for your live sound system or home recording setup can be a challenge. For this reason, it's important to familiarise yourself with the different cable types, and their intended applications.
IMPORTANT NOTE: Audio cables can either carry audio signals (XLR, Instrument Cables, etc) or audio + electrical current (i.e. speaker cables or XLR with 48V phantom power). This means it is imperative you are wiring your setups correctly and using the correct cables for the correct situations. Using an incorrect cable can destroy certain audio equipment/lead to irreversible damage. Be careful and be sure to read the product manuals for your equipment before you attempt to make any connections!
Balanced Vs. Unbalanced Cables
Before going any further, it's important to
know the difference between balanced and unbalanced cables:
Unbalanced Cables:

Are cables that consist of two main components internally: a signal wire and a ground wire. The audio signal will pass down the signal wire, and the ground wire will act as a shield against interference (such as radio waves or other electro-magnetic sources) picked
up along the cable run. Unbalanced cables perform best when run in lengths less than 20 feet (6m). Any cables run longer than 20 feet are likely to pick up unwanted interference/noise.
Balanced Cables:

Balanced cables function in a similar way to unbalanced cables, except they are made up of three internal components: 2 signal wires and 1 ground wire. Both signal wires 1 and 2 will send the audio signal along the length of the cable, except one of the signal wires will invert the phase of the signal. This effectively cancels out any interference added to the signal, meaning balanced cables can be run in lengths of up to 100 ft. (30m) without signal loss or interference issues.

COMMON CABLE TYPES:
XLR/Microphone Cables are likely a cable you are already familiar with, if you've done any recording, live performance or ever handled a microphone.
XLR (X = ground, L = Left, R = Right) cables are used to send balanced line-level or mic-level audio.

They are most commonly used to carry signal from a microphone/D.I. Box to a mixer/interface. They are also commonly used to send audio from a mixer to active speakers. As XLR Cables are balanced, you won't experience signal loss/interference issues in longer cable runs (up to 100 ft.)
1/4" (Instrument) Cable: You will have experienced these cables if you play guitar or bass, or have connected a digital piano or another similar instrument to a mixer or to an amp. Instrument cables are unbalanced and therefore function at their best in shorter cable runs (of up to 20 ft.)

Depending on the composition and materials used, instrument cables can cost as little as $15 and as much as $150. Our suggestion is to find a cable that uses Neutrik connectors, as these are the most common industry-standard when it comes to cables and cable connectors. An instrument cable can be identified by a single black band on the shaft of the jack, which separates the tip (usually connected to the signal wire) from the sleeve (usually connected to the ground wire). These cables are also sometimes referred to as TS Cables, referring to the two components (Tip, Sleeve).
Speaker Cables:
If your sound system uses passive speakers, speaker cables will be required. Speaker cables function differently than other cables, as they are designed to carry both audio current and electrical current. Speaker cables that are "thicker" or of a heavier gauge offer increased protection against interference and heat transfer (electricity causes heat!)

In most studio and stage applications, there are two common jacks used to connect speaker cables: 1/4" connectors and Speakon Connectors. The cable connector you will require will depend on the type of jacks on your passive speakers. Some speakers have both 1/4" and Speakon connectors whereas some may have only one or the other.
If you're connecting a power amp to passive speakers, be sure to have a read of this article which includes important information about properly matching a power amp to passive speakers.
TRS (Tip, Ring, Sleeve) Cables look similar to instrument cables, except they are balanced cables with 2 internal signal wires instead of just one. These are also known as

1/4" Stereo cables, and can be used for two functions - to send 1 balanced mono signal from end to end, or to send a stereo signal (Left & Right) from end to end. TRS cables are usually found in studio settings, and are usually used to connect rack-mounted/outboard equipment (such as FX processors, compressors, etc.) or studio monitors. They also have other applications as use as a stereo cable.
There are also Y-cable variations available that provide a TRS jack on one end, and then break away into two TS jacks. This is particularly handy in some applications, such as patching into a single-jack effects loop on a mixer or amp.
Final Thoughts:
Overall, there is no shortage of different cables and connector types on the market today. Cables and connectors come in many shapes and sizes, so it's important not only to familiarise yourself with the different cable types, but also their intended applications and use cases. When in doubt, be sure to consult the user manual for the equipment you own, which will provide specific information about what you will require.
By spending a little more upfront to buy a quality cable with industry-standard connectors, you can expect many years of service from it, providing you take good care of your investment. Be sure to wrap your cables neatly and avoid crimping or bending them sharply. For a few dollars online you can buy some velcro cable ties which are perfect when it comes to keeping your cables neatly rolled and stored. Walking/stepping on your cables will damage the internals, and will reduce their life expectancy. Be cautious when plugging in/unplugging the connectors, as any added strain will degrade the connectors/solder joints over time.
In a nutshell, protect your cables and they will serve you for many years to come!
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