What is the difference between sebaceous gland and sudoriferous gland?

Sebaceous glands are pear-shaped alveolar glands that secrete an oily substance called sebum, which moisturizes and waterproofs hair

Sudiferous glands are also called as sweat glands . They are small tubular structures present on the skin that produce sweat.They are of two types Eccrine and Apocrine sweatt glands.