Hashing
In plain terms
Mapping data to fixed-size values via a hash function.
Going deeper
Hashing converts arbitrary input into a fixed-size number used for fast lookups, deduplication, or integrity checks. Good hash functions spread inputs evenly.
Under the hood
Collisions are inevitable and must be handled; cryptographic hashes add one-way and tamper-evidence properties.
Examples
Hash tables, checksums, password storage, content addressing, caching keys.
Think of it like...
Like assigning each item a locker number computed from its name for instant retrieval.