What is the significance of the KeyValuePair<TKey, TValue> structure in Dictionary?

Short answer: KeyValuePair<TKey, TValue> represents a single item in a dictionary — a key-value pair. Used in: Iteration LINQ queries Return values from dictionary enumerators Example: foreach (KeyValuePair<string, int> entry in dictionary)

Example code

{ Console.WriteLine($"Key: {entry.Key}, Value: {entry.Value}"); }

Real-world example (ShopNest)

ShopNest caches product prices in a Dictionary<string, decimal> keyed by SKU so checkout can look up a price in O(1) instead of scanning a list.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.