Think of bitters like salt and pepper for a cocktail: a sprinkle of seasoning that balances out the flavors of a dish.\r\n\r\n\u201cBitters are a wonderful way to augment the flavor profile of a drink,\u201d says Lauren Mote, an award-winning mixologist and co-founder of Bittered Sling Bitters. \u201cBy adding a bitter component to other balanced ingredients, something magical happens. The cocktail dries out ever so slightly, the nuances of flavor bloom within the other elements. Finally, the drink tastes like a complete flavor, rather than a stop-and-start mix of components.\u201d\r\n\r\nThese little bottles are cocktail essentials. A few drops can make a drastic change to anything from a gin & tonic to an Old Fashioned.\r\n\r\n\u201cMake two Manhattans,\u201d says Mote. \u201cOne with two dashes of aromatic bitters (classic), and one without. It's astounding how drastically two milliliters can change things.\u201d\r\n\r\n\r\n\r\nBut what are aromatic bitters? Mote defines them as \u201chigh-proof infusions made with thoughtful ingredients.\u201d\r\n\r\nStyles of bitters will vary, but generally call for a blend of botanicals and spices. Some brands feature dozens of ingredients in each bottle. \u201c[Bitters] have complex, layered flavor profiles, thanks to the balance of herbs and spices being mixed and aged together,\u201d says Edoardo Branca, of amaro house Fernet-Branca.\r\n\r\nAromatic bitters were first patented in 1712, when doctors would prescribe them to treat stomach ailments. Some started to use them as hangover cures, as they would add a few dashes to wine or brandy to soothe aches and pains. As time went by, bitters transitioned from a remedy to a staple cocktail ingredient, though modern-day health food stores still stock bitters as digestive aids.\r\n\r\nWhat brands should you know? \u201cAngostura [bitters] and Peychaud's [bitters] are the granddaddies of bitters,\u201d says Mote. \u201cThey're the brands that have effectively created the category as we know it today.\u201d\r\n\r\nIn recent years, the bitters world has expanded to include countless varieties, from chocolate and habanero to cherry and crabapple. Here, an explainer of the two most commonly used brands, Angostura and Peychaud\u2019s, plus two other options to consider when creating cocktails at home.\r\n\r\n\r\nWhat are Angostura Bitters?\r\nIf the name Angostura doesn't ring a bell, the distinct bottle should jog your memory. It's the world's top-selling and oldest bitters brand in production, most recognizable by its oversized white label and bright yellow cap. The quirky label was initially a production fluke, but it\u2019s now the brand's distinguishing feature.\r\n\r\nIn 1824, Angostura bitters was invented by Dr. Johann Siegert in Angostura, Venezuela. At first, his intentions were purely medicinal. He declared his blend of 40 spices and botanicals a cure for stomach ailments, and he circulated the potion to the soldiers of Sim\u00f3n Bol\u00edvar's army.\r\n\r\n\u201cThe product's medical usage continued through the 1870s until Dr. Siegert's sons, the Siegert Brothers, took over the company and migrated to the island of Trinidad,\u201d says Mitch Cooper, Angostura's brand manager. \u201cOne of his sons, Don Carlos, realized that the complex flavors of Angostura aromatic bitters perfectly complemented the characters in a cocktail or food when incorporated\u2014or \u2018dashed\u2019\u2014in moderation.\u201d\r\n\r\nSiegert's recipe is still used today, but it\u2019s under tight wraps. It\u2019s said that only five people know the exact ingredients.\r\n\r\n\u201cThe secret mixture is infused with a high-proof spirit,\u201d says Cooper. \u201cWe then combine it with brown sugar, coloring and dilute it down to 44.7% alcohol.\u201d\r\n\r\nMany classic cocktails, like the Old Fashioned and Manhattan, call for a dash or two of Angostura to add bitterness and spice.\r\n\r\n\u201cYou can also add a few dashes to a glass of gin and find yourself drinking a lovely pink gin cocktail, a favorite of Queen Elizabeth II,\u201d says Cooper. Newer recipes, like the Bitter Last Word or the Trinidad Sour, demand a full mouth-puckering ounce of Angostura.\r\n\r\n\r\nWhat are Peychaud's Bitters?\r\nInvented in the 1830s by pharmacist Antoine Am\u00e9d\u00e9e Peychaud, the gentian-based, anise-forward Peychaud's Bitters has a distinctly New Orleans identity.\r\n\r\n\u201cDuring the daytime, Peychaud was prescribing the blend for those with anything from stomach aches to migraines,\u201d says Mote. \u201cBut during the evenings, Peychaud was acting somewhat of a bartender, combining his medicinal tincture, absinthe and brandy together. This became affectionately known as \u2018Peychaud's Cocktail.\u2019 \u201d\r\n\r\nThe cocktail caught on with the help of French Quarter coffeehouse owner Sewell Taylor, who used Peychaud's in his \u201cSazerac\u201d cocktail in the early 1800s. Today, Peychaud's Bitters is still a crucial part of a Sazerac.\r\n\r\n\r\nWhat are Orange Bitters?\r\n\u201cOrange bitters are a zesty blend of tropical oranges and spices,\u201d says Cooper. The orange notes come from dried zest of orange peels, typically from Seville or the West Indies, with spices of Gentian root, cinnamon, cloves, ginger and coriander.\r\n\r\n\u201cOrange bitters are a wonderful way to bloom flavors in white spirits, specifically gin,\u201d says Mote. She says orange bitters were called for in the original martini recipe, in addition to gin and white vermouth.\r\n\r\nCooper agrees. \u201cOrange bitters are the soul of an exceptional dry martini.\u201d\r\n\r\nYou can also add them to tropical-leaning drinks like margaritas and daiquiris, or try a dash of orange bitters in a pour of whiskey or Bourbon.\r\n\r\n\r\nWhat are Chocolate Bitters?\r\nA dash or two of chocolate bitters, commonly made with cacao nibs and spices, will add a subtle nuttiness to cocktails. While they might seem in the dessert realm, chocolate bitters play very well with sweet vermouth or aged spirits, like whiskeys or rums. Try them in cocktails like Manhattans, or with a dash of vermouth and soda for an easy, low-alcohol aperitif.\r\n\r\nAlso in the chocolate bitters family: mole bitters, made with chilies and cacao.