In Redis, LIST, SET, and SORTED SET (ZSET) are different data structures, each with specific characteristics and use cases:

🔹 LIST

Description:
A Redis LIST is an ordered collection of string elements, like a linked list.

Characteristics:

• Maintains insertion order.
• Allows duplicate elements.
• Supports push/pop operations from both ends (LPUSH, RPUSH, LPOP, RPOP).
• Indexable via LINDEX, LRANGE.

Use cases:

• Message queues
• Logs
• Stacks or queues (FIFO/LIFO)

Example:

RPUSH mylist "a" "b" "c"
LRANGE mylist 0 -1   # ["a", "b", "c"]

🔹 SET

Description:
A Redis SET is an unordered collection of unique string elements.

Characteristics:

• No order is guaranteed.
• No duplicates allowed.
• Fast operations for adding, removing, and checking membership.
• Supports set operations: SUNION, SINTER, SDIFF.

Use cases:

• Membership checks
• Tags or categories
• Unique collections

Example:

SADD myset "a" "b" "c" "a"
SMEMBERS myset   # {"a", "b", "c"}

🔹 SORTED SET (ZSET)

Description:
A Sorted Set is like a SET but with a score associated with each element, and elements are sorted by score.

Characteristics:

• Elements are unique.
• Sorted by a floating-point score (can be negative).
• Allows range queries by score or rank.
• Supports operations like ZRANGE, ZREVRANGE, ZADD, ZSCORE.

Use cases:

• Leaderboards (e.g., top scores)
• Priority queues
• Timestamped events

Example:

ZADD myzset 100 "Alice" 200 "Bob" 150 "Charlie"
ZRANGE myzset 0 -1 WITHSCORES  
# [("Alice", 100), ("Charlie", 150), ("Bob", 200)]

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