in reference to a menu of items priced and ordered separately, i.e. the usual operation of restaurants. This is in contrast to a table d'hôte, at which a menu with limited or no choice is served at a fixed price.
to order an item from the menu on its own, e.g. a steak without the potatoes and vegetables is steak à la carte
to describe a retail pricing model in which goods or services traditionally bundled together are separated out, putatively giving the consumer greater choice at lower cost. Examples include airline pricing where in-flight drinks or snacks are not complimentary, on-line music purchasing where individual tracks can be bought instead of entire albums, or pay television where individual channels can be ordered rather than a bundle of channels.