Frommer is a publisher of travel guides ... I'd say the person thought you were a really good guide.
They mean that the expression to the left of the sign is greater than or less than (as appropriate) the expression to the right of the sign.
"Mieux vaut tard que jamais" is a French expression that translates to "better late than never" in English. It conveys the idea that it is better to do something late than to not do it at all.
The expression, "is at most" is stating that there is no higher terms than what is being stated.
One expression describing a person who pretends to be morally better than he really is is "a whited sepulchre".
What is mean deviation and why is quartile deviation better than mean deviation?
It means that the number or expression on the left of the symbol is less that the value or expression to the right, or that they are equal.
A mathematical expression is a collection of numbers and variables along with mathematical operators - other than equalities or inequalities.
You might mean an inequality (with 'less than', 'greater than', etc). You might mean an expression.
Because gold is better than yellow
6x-5
I Am Better Than yoU
no but they have a sense of smell better than you or my eyes... i mean it