Saber and conocer are two verbs which are very often confused in Spanish as both can be translated in English as to know. Saber means to know a fact or to know how to do something. Most people find it easier to change the meaning of conocer in English to translate as to be acquainted with a person or a place. Note the first person singular or yo part of each verb is irregular
To know a fact is simple – yo sé
To know how to do something – yo sé + infinitive e.g. yo sé hablar inglés.
To know that – yo sé que
I know a person – yo conozco + a – e.g. yo conozco a Maria
I know a place – yo conozco Tenerife