À la carte /ɑːləˈkɑrt/[1] is a French language loan phrase meaning "according to the menu", and used
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.
The phrase was adopted into English in 1826, predating by a decade the common use of the French language loanword "menu".
https://en.wikipedia.org/wiki/%C3%80_la_carte
http://www.phrases.org.uk/meanings/9200.html