Although "by" typically points to the beginning of something, the term "1960s" is itself vague. "By the 1960s" will not be heard by a listener in the same way as "by 1960". The sentence may or may not say that the appliances were commonplace throughout the 1960s. The sentence is intentionally vague.

I agree with Ahmadi’s answer: it means the appliances were commonplace before the 1960s and during them too, not that they became commonplace only when the 1960s began actually.

Hi Kristin, In this context ‘by’ is closer to ‘in’ than ‘until’, however they slightly change the meaning of WHEN the situation happens. I look at it like this: ‘Labour-saving appliances were common place in the home BY the 1960s’ - Marks the BEGINNING of an occurrence. Labour-saving appliances had become popular once this time period arrived. ‘Labour-saving appliances were common place in the home IN the 1960s’ - Marks the MIDDLE of an occurrence. Labour-saving appliances have been popular throughout this time period. ‘Labour-saving appliances were common place in the home UNTIL the 1960s’ - Marks the END of an occurrence. Labour-saving appliances are no longer popular in this time period. Hope this helped!

In the context of your sentence, "by" means "in." So, the sentence "Labour-saving appliances were commonplace in the home by the 1960s" implies that labor-saving appliances had become common in households by the time the 1960s arrived. In other words, these appliances were already in widespread use during the 1960s.

Hi Lorena, thank you so much for your detailed answer! It has helped in that I'm now certain about the meaning. However, I still can't get my head around the fact that "by" does not indicate a deadline as in most temporal situations. 🧐