What are slots used for?

Question

I try to understand what slots are for. ethereum has same term but everything I read about slots are so abstract. From different solana docs, I read those

Solana has 432,000 slots per epoch which amounts to ~2 days. Each epoch has a randomly generated predefined leader schedule that defines which validator is expected to produce a block per slot. A slot can then either contain a block or not (skipped slot).

A slot refers to the period of time in which a slot leader produces ledger entries. The minimum slot time is 400ms. We display the time it took the current leader to ingest transactions and produce a block.

The period of time for which each leader ingests transactions and produces a block. Collectively, slots create a logical clock. Slots are ordered sequentially and non-overlapping, comprising roughly equal real-world time as per PoH.

All those are so abstract. can someone explain what it is used for? What is the logic behind it?

Answer 1

Slots and Epoch are simply units of time on Solana. A slot is the smallest unit, and 432000 of it makes an Epoch.

A slot can then either contain a block or not (skipped slot). A slot refers to the period of time in which a slot leader produces ledger entries. The period of time for which each leader ingests transactions and produces a block.

There's the concept of a leader in Solana. A leader for a particular period is the only validator that is allowed to produce a block.

Solana has a system that changes the leader frequently. The window of opportunity a leader has to produce a block before that privilege is re-assigned to a different validator is called a slot.