Princesses

Princesses are rulers of places in Equestria, even the whole of Equestria itself. All of the known princesses ever featured in episodes have been alicorns. Some fans have made princess ponies in their fanfic tins that d not ave a horn and wings altogether, even some that are Earth Ponies with no sign of a horn or wings, some have made princesses based on background ponies, antagonists, and protagonists, other characters in the show, and some that have abnormal powers. Some have drawn existing princesses as a school-age pony or a baby pony, and some with strange designs or abnormally sized body parts.

Exsisting princesses
Princess Celestia and Princess Luna] are two Exsisting princesses that raise the sun and moon. They rule Equestria, and Princess Celestia mentors Twilight Sparkle through her studies on the magic of friendship, while Princess Luna is more of a background character, while she has one episode based in herself, and there are no episodes based on Celestia. Princess Cadence is another royal princess, originally Twilight's babysitter when she was very young. She was first introduced in A Canterlot Wedding, Part One and has attracted many fans, even a large club based on her. Princess Cadence is also named Mi Amore Cadenza, but she requests to be called Princess Cadence in her wedding ceremony. Her first appearance in the show was when she was to marry Shining Armor but her wedding was disrupted when an impostor, a changeling called Queen Chrysalis, took her place and imprisoned her underneath Canterlot, in the Canterlot Caves which were once home to greedy Unicorns who wanted to claim the gems that could be found inside. She later imprisons Twilight Sparkle, seeing that she has her suspicions about her. The real Princess later returns the impostor to her real state, uses her and Shining Armor's love to repel her and her Changeling minions out of Canterlot, and has her real wedding.

Depiction in the series
Ruling Equestria All princesses that currently exsist in the series rule Equestria or a certain part of Equestria, such as the two princesses taking responsibility for the sun and moon ruling the whole of Equestria and Princess Cadence ruling just Canterlot. The three princesses have royal duties, and other royal guards and ponies to help them with those duties. The majority of these helping ponies wear armor, or special clothing apparently to identify them as royalty or helpers of royalty, such as the royal guards wearing special armor or the royal ring bearer for weddings wearing a special suit.