Space complexity
Measure of how algorithm memory usage grows with input size. Space complexity includes auxiliary space (extra memory beyond input). Analysis guides memory-constrained environment choices.
Real World
NASA's Mars rover has only 2 GB of flash memory, so engineers must choose in-place algorithms with O(1) space complexity rather than ones requiring large temporary arrays.
Exam Focus
Explain the space-time tradeoff explicitly — state what extra memory buys in speed, as mark schemes reward this link.
How well did you know this?