Dash

Dash operates a two-tier network: miners produce blocks while masternodes — operators who lock a substantial collateral — provide additional services and govern a treasury funded from the block reward. That second tier is what distinguishes it from a straightforward proof-of-work coin.

Masternodes require capital at risk

Running one demands locking a fixed, substantial amount of DASH. That collateral aligns operators with the network's value and limits how cheaply the second tier could be attacked. It also concentrates governance among those able to afford the requirement, which is the corresponding cost.

InstantSend addresses the confirmation problem

Masternode quorums lock transaction inputs so a payment can be considered settled in seconds rather than after multiple blocks. For retail payment use this is the difference between usable and impractical, and it is a genuine solution to proof-of-work's slowest property.

Mixing is optional and CoinJoin-based

PrivateSend combines amounts from multiple users to obscure transaction history. It is opt-in and less comprehensive than the cryptographic approaches other privacy coins take. As with any optional scheme, its effectiveness depends on how many others are mixing at the same time.

A self-funding treasury

A portion of every block reward goes to a treasury, with masternode operators voting on which proposals receive funding. The network pays for its own development without depending on a foundation or external funding, and the funding decisions are recorded on-chain.

Where it stands

Dash was among the first to solve fast confirmation and self-funded governance, and both ideas have since appeared elsewhere. Its optional mixing is weaker than dedicated privacy designs, so it is better understood as a payment coin with governance than as a privacy coin.