A steroid hormone is a steroid that acts as a hormone. Steroid hormones can be grouped into 2 classes, corticosteroids (typically made in the adrenal cortex, hence cortico-) and sex steroids (typically made in the gonads or placenta). Within those 2 classes are 5 types according to the receptors to which they bind: glucocorticoids and mineralocorticoids (corticosteroids) and androgens, estrogens, and progestogens (sex steroids). Vitamin D derivatives are a sixth closely related hormone system with homologous receptors. They have some of the characteristics of true steroids as receptor ligands.