I have always used
\geq, but recently saw a document where the person uses
Once compiled, they look the same, but I searched to see if there was any difference between the two or a guideline as to which one to use, and most places say they are the same, but this source says
For greater than or equal to use the \ge command. The \geq command means greater than or equivalent to.
which makes no sense to me.
The question is then: are there any differences between the two, or any recommendation as to which one to use (what I have in mind is, for example, the case of
\[ \], where only the second option in each case should be used).