The two main classes of angiosperm are monocot and dicot. They differ from each other in many ways. The flower, roots, leaf venation pattern of monocot is different from dicot.
Monocots:
They have single cotyledon.
They have parallel leaf veins
Vascular bundles are usually completely arranged
They have fibrous root system
Floral parts are usually in the multiples of three
Dicots
They have two cotyledons
Vein pattern are usually net like
Vascular bundles are arranged in ring
They have tap root system
Floral patterns are usually in the multiple of four or five.