They are used in different situations.
§ Knowledge, facts
Yo sé donde vive el chico.
I know where the boy lives.
(I have knowledge of the fact.)
§ To know how to do something.
Yo sé hablar español.
I know how to speak Spanish.
Conocer is used to imply:
§ Acquainted with
Yo conozco a María.
I know Mary.
(I am acquainted with her.)
§ Familiar with
Yo conozco South Lake Tahoe.
I know South Lake Tahoe, I am familiar with the area.
§ To meet
Yo quiero conocer al chico.
I want to meet the boy.
saber
conocer
Both verbs are irregular in the yo form.
yo
sé
conozco
tú
sabes
conoces
él, ella, usted
sabe
conoce
nosotros
sabemos
conocemos
vosotros
sabéis
conocéis
ellos, ustedes
saben
conocen
I know how to ski.
Yo sé esquiar.
I don’t know how to speak French.
No sé hablar francés.
Do you know how to get to her house?
¿Sabes llegar a su casa?
She knows how to dance.
Ella sabe bailar.
We know how to use the computer.
Sabemos usar la computadora.
They know how to cook.
Ellos saben cocinar.
I know José.
Yo conozco a José.
She knows the teacher.
Ella conoce a la profesora.
Do you know the man?
¿Conoces al hombre?
We know the children.
Conocemos a los niños.
They know my cousin.
Ellos conocen a mi primo.
I know Mexico well.
Conozco México bien.
Personal a
When the direct object of a verb is a person, a must go in front of the person.
Direct object = who or what the verb does.
Whom do I know?
I know Mary.
¿A quién conozco?
Conozco a María.
We know Raul.
Conocemos a Raul.
I love Carmen.
Quiero a Carmen.