Food that has been preserved in a seasoned brine or vinegar mixture. Any food can be pickled (verb), but a "pickle" (noun) refers to a pickled cucumber. Pickles can be sour, sweet, hot or flavored. There are pickled vegetables (cucumbers, pearl onions, cauliflower, baby corn, watermelon rind) as well as various pickled fish, herring, pig's feet, etc. Pickling is one of the oldest methods of preserving foods. Pickling is the preserving of food in an acid (usually vinegar), and it is this acid environment that prevents undesirable bacteria growth. However, how and what kind of acid gets into the liquid is what can cause some confusion about the use of salt. Most pickled foods are salted or soaked in brine first to draw out moisture that would dilute the acid that is added to 'pickle' the food. (1) Vinegar can be added directly to the liquid that the food is placed in. (2) The food can be place in brine (salt and water). Even though it may seem that pickling can be done with either an acid (vinegar, etc.) or salt, that is not strictly true because the amount of salt in the solution is carefully measured to allow natural fermentation which produces lactic acid. So pickled foods that are made with brine (salt and water) are really made with an acid- - but instead of directly adding acid, conditions are created so that the fermentation creates its own acid. This is a tricky process because just enough salt needs to be added to prevent the growth of undesirable bacteria, and the correct temperature maintained, to still allow the growth of several specific bacteria that produce lactic acid. (3) Some cucumber pickles are made with a combination of both methods. They are soaked in a strong brine with vinegar added in specific proportions so that they still ferment and produce additional acid (lactic acid).