The present perfect tense is a compound tense using haber with a past participle.  (Haber is only used as a helping verb; it is never used to show possession.)  This tense can be translated as have or has done something.  Please note that the preterite tense is used more often than this tense when expressing the past.

Past participles are formed by dropping the infinitive ending, and adding these endings:

The following verbs have irregular past participles:  abrir (to open) - abierto (opened); escribir (to write) - escrito (written); morir (to die) - muerto (died); poner (to put) - puesto (put); ver (to see) - visto (seen); volver (to return) - vuelto (returned); decir (to say) - dicho (said); hacer (to do) - hecho (done).

No han vendido la casa.  They have not sold the house.
Dónde ha puesto Ud. la llave?  Where have you put the key?
Hemos gastado mucho dinero.  We have spent a lot of money.
Qué ha dicho Ud.?  What did you say?