Shipping is when you like the idea of two people or characters being in a relationship together. It doesn't necessarily have to be romantic, but most are. Once you have your two (or more) characters, you can create or find a ship name for them, which is a mashup of their names into one word.
It's not always a mashup of their names. Like the ship of Finn and Flame Princess from Adventure Time is called SmokeyBear. And the entire Invader ZIM (it's an old show from Nick) fandom has ship names like ZaDR (Zim and Dib Romance) and GaMR (Gir and Mimi Romance).
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