Spanish Simple Past
(a.k.a Indefinido, Pretérito, Spanish Preterite)
The Spanish Simple Past (El Pretérito Indefinido) describes past actions in a way that conveys the sense that were completed/finished, as opposed to ongoing, continuing, habitual, etc. It's one of the three most commonly used Spanish past tenses, along with El Pretérito Perfecto and El Pretérito Imperfecto. (But there are many more!)
The Indefinido is the direct equivalent of the English simple past (e.g. I did).
See also: Spanish Past Tenses and All Spanish Tenses