At-Arms
An At-Arms, mechanically equivalent to a Page, is a sworn individual similar to a Squire, but differentiated in the rulebook and in Amtgard custom. They are the equivalent of a Page in the Order of Precedence.
In Amtgard
Officially, there is no difference between At-Arms and Pages, as neither is officially recognized in the Order of Precedence or most Corporas. Some kingdoms define a man-at-arms as some one who fights, while a page is a non-combatant. Some kingdoms eschew one in favor of the other. Some kingdoms allow squires to take a man-at-arms, and a noble to take a page. In some places, children too young to fight are pages, while everyone else is a man-at-arms.
The term 'Page' also sometimes refers to the kind folks that pick up spent equipment for you on the battlefield. Non-fighting pages may retrieve spent equipment, but may not retrieve or carry new or extra equipment.
Symbols
At-Arms wear a black belt. In some Kingdoms this is further established with silver trim but many places don't require or use it.
Pages wear a yellow belt. Garb consisting of their master’s device is optional.
Men-at-arms and Pages
Officially, there is no difference, as neither is officially recognized in the Order of Precedence or most Corporas. Some kingdoms define an At-Arms as some one who fights, while a page is a non-combatant. Some kingdoms eschew one in favor of the other. Some kingdoms allow squires to take a man-at-arms, and a noble to take a page. In some places, children too young to fight are pages, while everyone else is an At-arms.
In Real Life
Historically, a man-at-arms and pages were fighters and servants employed by an army, lord, or individual knights. Although this is theoretically a mentor-student type relationship, there are a multitude of reasons that a squire might take a man-at-arms.