Sorry, F.O., that explanation of balanced vs. unbalanced just isn't right, although good on you for responding to the OP's remark.
Unbalanced = typical consumer cables and connections. Think of a cable in a hi-fi system that ends in an RCA ("pin") plug, with its "hot" center wire and surrounding shield/ground. The shield carries just as much audio signal current as the center wire does; that's how the circuit is made. It's a cheap but effective approach where the source impedance is low, the cable runs are short, and there's no big concern about interference.
Balanced = typical professional cables and connections, usually with XLR connectors. The cable shield is strictly a shield--a conductive enclosure which itself connects the enclosures of the equipment on both ends of the cable--to keep any interfering signals out. The audio signal current doesn't run in the shield at all; instead, it runs in a pair of wires within the shield. One of those wires is the "hot" and the other might be called the "cold," but neither one is connected to the shield, and technically they must have the same impedance w/r/t signal ground as each other.
Those inner wires are generally twisted together, so that any interfering signals that do make it through the shield will be induced into both wires equally and "in phase". At the receiving end of the cable, the balanced input is sensitive only to the moment-to-moment voltage differences between the two inner conductors (= the intended audio signal); anything that they carry in common (= interference or, if DC, perhaps the residual from phantom powering) cancels out and is ignored. So balanced connections are designed to suppress interference, and that's why professionals use them. (Interesting fact: The twisting of the conductors and the balanced input circuit suppress more interference than shielding does.)
--Not directly a function of balanced vs. unbalanced, but: Another thing that's typical of professional equipment is that it uses higher signal voltages than consumer equipment. (This, too, is part of the war on noise due to interference; if all else fails, drown the noise out with high signal levels.) For example, typical consumer gear might use half a Volt as the nominal level for "line in" or "aux" signals, while studio components typically use +4 dBu, which is a little above 1.2 Volts. The discrepancy can be much greater with microphones, though, where professional condensers might put out 10 to 20 times the voltage that a consumer (dynamic or electret) microphone might produce for the same sound level. Thus the concern for overload, especially when recording loud program material.