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+# Distributed Cache (Focus: Hashing & System Logic)
+
+- Question: Implement a Cache Router
+
+  Level 1 (Easy - Modulo Hashing): Write a function that maps a key (string) to one of N servers.
+
+      Task: Implement getServerIndex(key, serverCount).
+
+      Expected Logic: Simple hash modulo: hash(key) % serverCount.
+
+      Critique: The interviewer will ask, "What happens to the existing keys if we add one server (change N to N+1)?" (Answer: Almost all keys get remapped, causing a massive cache miss storm).
+
+  Level 2 (Medium - Consistent Hashing): Solve the remapping problem. Implement a ConsistentHash class.
+
+      Task: Map servers to points on a circle (0 to 360 degrees or a large integer range). Map keys to the same circle. A key belongs to the first server it encounters moving clockwise.
+
+      Goal: Prove that adding a server only requires remapping the keys that fall between the new server and its predecessor.
+
+  Level 3 (Hard - Virtual Nodes): The servers have uneven capacity, or the data distribution is skewed (some segments of the ring have way more keys).
+
+      Task: Modify the class so that each physical server exists at multiple points on the ring (e.g., "Server A" is at positions 10, 150, and 290).
+
+      Goal: Distribute load more evenly and handle "hot spots" better.
+
+---
+
+Questions:
+
+  - Async
+  - Threads
+  - DB 
+  - Cache
+  - KV
+  - Distribution
+
+
+--- 
+
+FE
+
+ - Fetching URL
+    - Storing it as useMemo and what not.
+