This video discusses when to take Social Security Retirement Benefits for the common case where a husband had higher earnings than the wife.
The strategy discussed here is to have the wife take reduced benefits early, while having the husband delay his receipt of retirement benefits.
The key here is that when the husband passes away first (a common occurrence), the wife will see a step up from her reduced benefits to her spouse's higher benefit level.
This also discusses a "File and suspend" strategy to maximize benefits.