The term 'aspect' according to grammaticians generally describes whether the action is incomplete or ongoing.
I think it's helpful to think of uses rather than tenses
Past tenses
The English past simple can be both perfective and imperfective;
- Actions completed at a specific time (e.g. yesterday, last night, at+time) in the past (perfective)
- Series of completed actions in the past (perfective)
- Durations in the past; past+duration, similar to preterite+duration (perfective)
- Past habitual actions; interchangeable with 'used-to' (imperfective)*
- Past facts or generalisations; interchangebale with 'used to' (imperfective)*
Why learners of English struggle with the past tense
The reason the English past simple isn't directly translatable is because there are imperfective uses of this tense. A lot of those imperfective uses are substituteable by 'used-to+vocab'.
How different languages express aspect
In English it's not all that clear. In Spanish aspect is clearly marked in the two past tenses the preterite (preterito perfecto) and the imperfect (preterito imperfecto). In the Slavic languages such as Russian, verbs come in pairs. In Greek (Hellenic languages) there's a different stem to express perfective aspect known as the aorist stem rather than a different verb. It's a bit like the Slavic languages except there's just one verb. The past endings are the same. Greek has a present and non-past just like the Germanic and Slavic languages, in that the future tenses are 'compound' (well in the Slavic languages (except Bulgarian & Macedonian) the present forms of perfective verbs mark the perfective future).
Today I learned the difference between a 'preterite' and an 'aorist' (perfective past). An aorist has a different stem to the base form (infinitive form or for languages that don't have an infinitive, the present 1st person 'I' form as in Greek and Bulgarian). A preterite tense simply takes the stem of of the base form and marks aspect by personal markers.
Thought I'd share this grammar nonsense.