Welcome to the Steven Universe thread!
If you're a veteran to the show, we ask you to keep major plot points properly formatted to prevent spoilers. If you're unsure, well, err on the side of caution please!
Meanwhile, to introduce any newcomers to this show, a quick glance at wikipedia would tell you that Steven Universe is "an American animated television series created by Rebecca Sugar, former storyboard artist, writer, and composer for Adventure Time" that premiered on Cartoon Network on November 4, 2013. As the show begins, it covers the oft magical adventures (and sometimes more mundane daily shenanigans) of said Steven Universe, a young boy who inherited the gem of his mother, Rose Quartz. This makes him part of a group known as the Crystal Gems, a group of mystical warriors who draw upon the power of their own gems in order to protect the Earth from anything that would threaten it.
You can see Rebecca Sugar explain the premise herself here:
A quick guide to the Crystal Gems, the main characters:
The titular character, Steven is a goofy, inherently kind hearted, and boundlessly optimistic kid - which makes him the youngest member on the team, and thus the one with much to learn about his universe. The other gems as such are both his family and his teachers, and through them he must come to understand what it means to be both human and gem as he struggles not only with typical issues of mortal maturity but the magical powers that lie latent inside himself.
A disciplined warrior and leader of the Crystal Gems, she is coolness personified and as such often serves as the group's foundation by being so level headed despite being sparse with words. Physically powerful, her magical powers emanate from the red gemstones in her palms, which she uses to form giant gauntlets for battle.
Impulsive, passionate, and wild, Amethyst is a stark contrast to Garnet. Blatantly joyous and carefree, Amethyst often chums around with Steven in playful ways closer to that of a sibling than a parent. Her gem is embedded in her chest, where she pulls a studded whip when its time to get serious.
Intellectual and rigidly rules minded, Pearl is the one most prone to bouts of motherly concern for both Steven's safety and future. She lives for structure and logic, and can be easily flustered when anything flies in the face of that (most often in the form of Amethyst's spontaneous behaviors). To fight, she smoothly manifests a long spear from the gem in her forehead she wields with the fluidity of a graceful dancer.
So, now you're thinking "Ok, so this is all well and good, but why should I watch?"
The show comes highly acclaimed for a reason. It is a well written (and thoroughly planned) program that manages to evoke more than just laughter from simple comedy. Further, much like Adventure Time before it, the world opens up as it goes on, and the history of the characters can easily keep one glued to the screen even when an episode is merely a plain day breaking up an often fantastical lifestyle. I'll be the first to admit that it may not click right away - but know that it only gets stronger. So why not give it a chance?
You may just find yourself enthralled in Steven's universe.