Plain English.
No jargon for jargon's sake.

Self-custody means the private keys to your crypto live on a device you control. Not on Coinbase, not on Binance, not in a custodian's vault. The upside is sovereignty. The downside is the responsibility never leaves your hands.

A seed phrase is the master backup. Anyone who reads it can drain your wallet from anywhere on earth. Keep it offline, in two physical places, never in a photo, never in cloud storage.

When you sign a transaction with a hardware wallet, the private key never leaves the chip. Your laptop sees the signed result, not the secret. That is the entire pitch.

A 2-of-3 split means three people each hold a piece, any two can recombine the original, no single piece reveals anything. It is how you let a spouse, lawyer, or sibling participate in recovery without trusting any of them alone.

A dead-man-switch system that lets a designated recipient access funds after a verified inactivity period, with multi-party challenges that prevent abuse while you are still alive.

NFT carries the cultural baggage of cartoon-ape speculation. DOT names the actual primitive: a unique on-chain record of ownership tied to a specific work, asset, or right. We use DOT in the academy because the word should match the function.

Modern wallets show truncated addresses (0xabc...xyz). Attackers generate addresses with the same first and last few characters, then push tiny transactions into your history so the bad address appears in your recent-paste list. Always verify mid-characters.

Anything that asks you to sign, paste your seed, or approve a transaction. Real phishing rarely says “urgent.” It says “routine.” Slow down before you click.

No account, no custody. You connect your wallet, the protocol matches you against a pool, and the trade settles on chain. Lower fees, more responsibility.

On a DEX, the price you see and the price you get can differ if the pool moves while your transaction confirms. Slippage tolerance lets you cap that delta. Set it tight on liquid pairs, looser on thin ones.

Anyone who orders the next block can sometimes squeeze a few cents out of your transaction by sandwiching it between their own. MEV-protected RPCs and private mempools reduce the surface.

Treasury bills, real estate, commodities, all represented as on-chain instruments. RWA is the answer to “crypto is just speculation.” It is also the bar for diligence: if there is no audit trail, there is no asset.

A private key is the number that authorises a transaction. Ownership in this system is not a record of your name anywhere, it is possession of this secret. That is the whole reason custody advice is so blunt: there is no appeal, no reset, and no support desk that can override it.

Cold means the signing key has no path to a network. The trade is deliberate: you accept friction on the way out so that remote compromise stops being possible. It is the right home for the money you are not touching this month, and the wrong home for the money you spend weekly.

A 2-of-3 multisig needs two of three keys to sign. It removes the single point of failure that one key represents, and it replaces it with a coordination problem you have to actually rehearse. An unrehearsed multisig is a way to lose funds slowly rather than quickly.

A passphrase, sometimes called the 25th word, derives an entirely separate set of keys from the same seed. Get one character wrong and you land silently in a different empty wallet rather than getting an error. That silence is the failure mode: nothing tells you that you are in the wrong place.

A program deployed on chain that anyone can call and that can custody assets. It does what it says, which is different from doing what you assumed. Most losses attributed to smart contracts are not broken cryptography, they are correct code doing exactly what was written.

The peg is a claim, not a law. What backs it, who audits that backing, and whether you can actually redeem it decide whether the peg holds under stress. The March 2023 USDC weekend is the standing example: nothing about the token changed, and it still traded well below a dollar while the mechanism that would have arbitraged it back was closed.

An exchange, a broker, or a qualified custodian holds the keys and owes you a balance. That is a credit relationship, not possession: you hold a claim on them. Custody can be the right answer, and it is a different risk rather than no risk, which is the part that usually goes unsaid.

A blockchain cannot read the outside world, so an oracle feeds it prices and other facts. That makes the oracle part of the security model rather than plumbing: if the feed can be moved, anything that liquidates or settles against it can be moved with it.

A bridge locks an asset on one chain and issues a representation on another. That design concentrates value in one contract with complex trust assumptions, which is why bridges account for some of the largest losses in the sector rather than a scattering of small ones.

When a leveraged position falls past its maintenance threshold, the protocol or exchange closes it and takes the collateral. It is arithmetic, not a judgment call, and it is computable before you open the position. Learners who compute the level first stop being surprised by it.

Leverage multiplies the outcome in both directions and it shortens the distance to a liquidation. The number people quote is the multiple, the number that matters is the price move that ends the position, and those are not the same thing.

Drawdown measures the fall from a peak to a trough, and it is the honest counterpart to a return figure. Recovery is asymmetric: a 50 percent drawdown needs a 100 percent gain to get back level, which is the arithmetic most performance claims quietly leave out.

Bids on one side, asks on the other, and the gap between them is the spread. Depth is the part that matters under stress: a book can look busy and still have nothing behind the first few levels, so a large order walks the price rather than filling at it.

A market maker posts a bid and an ask and profits from the difference while carrying inventory risk. They provide most of the visible liquidity in normal conditions, and they are under no obligation to keep quoting when conditions stop being normal, which is exactly when depth disappears.

Supplying two assets to a pool means the pool rebalances against you as their relative price moves, so you end up holding more of the loser. It is only impermanent if the prices come back. The name is optimistic and the loss is entirely real when you withdraw.

Sizing is the part of risk you actually control. Entry and exit are guesses about the market, size is a decision about yourself, and it is what determines whether a run of losses is an inconvenience or the end of the account.

Multiply each outcome by its probability and add them up. It is the tool that separates a good decision from a good result: a positive expected value bet can lose, and a negative one can win, and neither outcome tells you whether the decision was sound.

The base rate is the background frequency you should start from. Ignoring it is the most common way a confident estimate goes wrong: a vivid story about one project displaces the far duller fact of how often projects of that kind fail.

Impersonation, urgency, authority and helpfulness, used to get you to act against your own interest. It is the most productive attack class in this field because it does not require breaking anything: the system works exactly as designed and you are persuaded to operate it.

You commit tokens to a validator and earn a share of issuance. The yield is not free: you take on lock-up, the validator's operational risk, and in some networks a penalty if they misbehave. Whether the yield beats simply holding depends on what the token does over the same period, which the yield figure never tells you.

Every course in this curriculum starts with a real incident: what happened, what the mechanism was, and the exact point where a different decision would have changed the outcome. Every one carries a source you can check. If we cannot source it, we do not teach from it.