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Courtship rituals have been practiced in many forms over the years. These behaviours aren't exclusive to humans – there are similarities with mating rituals in the animal kingdom. For example, when a man attempts to gain the attention of a romantic partner, he might put on charming clothing and "flaunt his feathers" – just like a male peacock shows his ornamental feathers to attract a female peahen. Two people hold hands to convey a message of their close relationship, while African elephants caress each other and intertwine their trunks in the courtship phase. Couples have dinner together on a date, while many birds also share food in the name of romance.

Numerous rituals showcase the basic instincts of all living creatures; for humans, however, the approaches tend to be a bit less clinical and a bit more fun. During the Victorian era, a pocket-sized calling card became part of the romance of courting. This custom began in France in the 1800s, and quickly spread across Europe and the US as a formal means to maintain social contacts.

For a Victorian gentleman who aimed to start a conversation with a lovely lady, or simply wanted to walk her home, he would often use an acquaintance card. According to the Encyclopedia of Ephemera, the acquaintance card was "used by the less formal male in approaches to the less formal female. Given also as an 'escort card' or 'invitation card', the device commonly carried a brief message and a simple illustration. Flirtatious and fun, the acquaintance card brought levity to what otherwise might have seemed a more formal proposal. A common means of introduction, it was never taken too seriously."