These are highly decorated cloths which can be hung from either a vertical or horizontal pole. The decorations bear the coat of arms or other emblem of a regiment or organisation. In any location they are regarded with honour and great respect.
(Of course, many call the flags banners but hey, what’s in a name! What I have described is just one way of describing them. Depends what you are using the implement for. It doesn’t really matter but for the purposes of clarity on this website, flags will be the things you hold in your hand and wave, banners will be things you hang on a bar and/or put on the wall.)
Banners, standards and flags played an important role in military history. Their function is to embody the spirit of the regiment, to provide a focus of belonging and loyalty amongst the troops. They were (and are still) paraded before the troops regularly and with great ceremony to ensure that each man can readily recognise and bond with the colours of his regiment and therefore know whom to follow on the battlefield or where their home base is.
The best known modern equivalent is probably the athletes parading their national flags at the opening of the Olympic Games. And when one of them wins gold and sees their flag raised not just before the stadium but before millions world-wide, what emotion is portrayed! How special is that!