The term "silver lining" refers to a positive aspect or hopeful side of a situation, especially when the situation seems bad or unfortunate. It suggests that even in difficult times, there can be something good that can be recognized or hoped for. The idea is that just like the silver lining on a cloud indicates that behind it, there may be sunshine or clearer skies, similarly, positive outcomes can emerge from adverse circumstances.
The phrase "silver lining" originates from the 19th century, deriving from the imagery of clouds that appear gray or dark, but have a brighter, radiant edge which appears silver when illuminated by sunlight. The metaphorical use of the phrase emphasizes optimism and finding good in hard times.