What are the different between regular and irregular verbs in past?

What are the different between regular and irregular verbs in past? 

Regular verb: I learn easily. I learned that material yesterday. (For the verb “learn,” “learned” is both the simple past and past participle).

Trabajar = work = worked (pasado)= regular

Irregular verb: I hurt my foot today. I hurt my foot yesterday. (For the verb “hurt,” “hurt” is both the simple past and past participle. You would not write “I hurted my foot yesterday”).

Beber = drink = drank ( pasado) = irregular