XLR, Balanced, same thing???

I know that XLR is a type of connector, but what is balanced? I mean I know that there are balanced inputs on amplifiers that aren�t truly balanced at all. Does this also apply to cables as well? I guess my question is, just because a cable has the XLR type of connector, does it mean that it is balanced ? I would also like to know if all cable companies follow some sort of standard when it comes down to the pins on the cables, i.e. is pin number 1 always ground no matter what cable you use? What about the components used, do the manufacturers follow the same rule of thumb?

Balanced means that there are two signal lines, of opposite electrical phase and equal amplitude. Neither is referenced to ground. The most common balanced audio connector is XLR. (Unbalanced has one signal line referenced to ground.)

However, as you indicate, some XLR inputs and outputs are not balanced. (I just reviewed a preamp with an unbalanced XLR input and an XLR output that can be ordered balanced or unbalanced.) And, yes, pin1 is generally ground, pin2 is (+) and pin3 is (-) in the US.
Having XLR connectors on a cable does not necessarily mean that they are balanced. If you have need of a truly balanced cable I would pay special attention to the issue to make sure you are getting what you need. There seem to be multiple standards regarding the pin assignments that would affect the phase relationship of the cable. Marantz refers to European and US standards that are of opposite phase. I am not sure about the ground pin issue, but I would be sure to specify exactly what you are expecting prior to purchase or commission.

Thanks for the explanation. I’ve tried several cables with xlr connectors and much to my surprise some of them were noisier than others. Some of which were DEAD quiet, I mean, no hiss from the speakers when all the components were on with no music playing, at any volume, and much to my surprise two of which sounded as though the music were out of alignment. Is this what out of phase means? I don’t know if this makes any sense but that’s what I heard.
Since I do not have adequate knowledge to answer your question I have provided the link below for a short explanation.

Brief explanation of phase concerns at Audio Asylum
Phase refers to the arrival times of the two signals, the + and the - signals. If the wires are identical in length and have the same geometry and insulation, the signals will arrive at approximately the same time. If there is skew between the two signals, this will introduce distortion because they are subtracted from each other at the input buffer. If one cable sounds better than the next, this may be due to differences in skew, but it is more likely a difference in capacitance.