Chia seeds are the edible seeds of Salvia hispanica, a flowering plant belonging to the mint family. They are small, oval, grey/white/black seeds. Chia seeds are a source of Omega-3's.
Chia seeds are hydrophilic, meaning that they can absorb up to 12x their weight in liquid. Soaking the seeds creates a thick, gluey coating that gives it a gel-like texture.