SOH CAH TOA is an easy way to remember how to find the sine, cosine, and tangent values for a triangle.
SOH is how to find sine.
Sine is opposite over hypotenuse. That is, sine equals the length of the opposite side divided by the longest side of the triangle.
CAH is how to find cosine.
Cosine is adjacent over hypotenuse. That is, cosine equals the length of the adjacent side divided by the longest side of the triangle.
TOA is how to find tangent.
Tangent is opposite over adjacent. That is, tangent equals the length of the opposite side over the length of the adjacent side.