When the first human landed on the moon, millions of people sat in front of their TV sets.
When I was young, I did not want to go to school.
When I wrote a math test, I was always very nervous.
Whenever I came home late, my father got very angry.
The sentence introduced with the conjunction als (when) expresses a relationship to the time in which the action is performed. The conjunction is characteristic of one-time actions in the past that do not repeat. If a certain action in the past happens or repeats multiple times, the conjunction (wenn) is used. The word immer (always) emphasizes the repeatability of the action.