1. Comparatives
Two nouns may be seen as having more, or less, of a characteristic than another. To express this, the Comparative construction is used:
When one noun has more of a characteristic than the other, you use the formation using the appropriate adjective or adverb : más + adjective + que
Juan is taller than Luís.
Juan es más alto que Luís.
Juan and Enrique are taller than Luís.
Juan y Enrique son más altos que Luís.
Ana is shorter than Luís.
Ana es más baja que Luís.

2. When one noun has less of a characteristic than the other, you use the formation using the appropriate adjective
menos + adjective / adverb que:
Enrique is less intelligent than Héctor.
Enrique es menos inteligente que Héctor.

3. Some adjectives have irregular comparative forms:
bueno (good) → mejor (better)
malo (bad) → peor (worse)
viejo (old) → mayor (older) (with people)
(más viejo que with things)
joven (young) → menor (with people)
(más joven que with things)

4. My book is better than your book.
Mi libro es mejor que tu libro.
Ana is younger than Luisa.
Ana es menor que Luisa.
Beto is older than I.
Beto es mayor que yo.

5. Adverbs are compared in the same way as adjectives:
She answered more politely than he.
Ella contestó más cortésmente que él.
Ana runs faster than Elena.
Ana corre más rápida que Elena.

6. His class is more fun (divertida) than her class.
Su clase es más divertida que su clase.
Beto’s house is newer than my house.
La casa de Beto es más nueva que mi casa.
History books are less interesting than mystery novels.
Libros de historia son menos interesantes que novelas de misterio.
Manolo plays his music louder than I.
Manolo toca su música más ruídosa que yo.