Lamport timestamps tell us one useful thing: if event A caused event B, then A gets a smaller Lamport timestamp than B.

But the reverse is not true. If A has a smaller Lamport timestamp than B, that does not prove A caused B. They may have happened independently.

Vector clocks solve that gap. Instead of one counter, a vector clock keeps one counter per participant. That lets the system answer a richer question:

Did one event include the other event's history, or did the two happen independently?

This chapter covers the update rules, how to compare vectors, how version vectors help detect conflicting writes, and the practical limits around size, membership, and cleanup.