Differences between Vitamin A, Retinol, Beta-carotene

Retinol is basically pure Vitamin A.

When we eat foods containing beta carotene - found in carrots and other vegetables - the body converts it into Vitamin A (Retinol).

Retinol is also found in fish oils, eggs and butter. It stimulates skin cell growth and builds collagen. Lack of Retinol can result in dry, tough and sometimes peeling skin.

Extracted from:
http://www.dailymail.co.uk/health/article-24933/Is-Retinol-miracle-ingredient.html