How it all connects: one user journey
About 1837 wordsAbout 6 min
You now have seven pieces. This is where they become one picture.
This page is a preview, not a lesson
Roughly half the steps below are taught in Weeks 2 and 3. Each is marked and linked to where it is covered.
You are not expected to understand them yet. You are expected to finish the week able to say "I know what that step is for, and I know which week explains it."
You will not do this journey
It involves real money and real risk, and nothing in this programme requires either. It is here to show how the pieces fit — nothing more.
Learning objectives
- Trace one possible path from a bank account to an on-chain position and name each step
- Identify which steps you already understand and which are still ahead
- Explain, at each handover, what changes about who you are trusting
- Point to the week that covers each step you have not met yet
Core
The journey
This is one deliberately complex example, not the sequence every Web3 user follows. A bridge appears only when value needs to move between networks, and an explorer or dashboard is for observing activity rather than receiving assets.
✅ means you have covered it. → means it is ahead of you.
Step by step
Watch the "what you are trusting" line at each handover. Read the rows as branches in the example, not as a mandatory queue.
| Step | What happens | What you are trusting |
|---|---|---|
| Fiat → exchange | Money moves from a bank into an exchange account. A normal regulated relationship: KYC, an account, a company holding your funds | The exchange, entirely. You have a claim, not an asset |
| Exchange → USDC | Fiat converted to a stablecoin. Dollar value that moves at blockchain speed | The exchange, plus Circle — the issuer holding reserves. A new assumption, quietly added |
| Exchange → wallet | Withdrawn to an address you control. Custody moves from a company to a person | You control custody. The exchange no longer controls the wallet, but token-level controls may still exist — for example, a stablecoin issuer may be able to freeze its token |
| Wallet → chain | Assets sit on Ethereum, or on Base, an Ethereum L2 that handles activity separately while relying on Ethereum for important settlement/security. Lower fees are a common benefit; the route does not require a bridge | The network, and the L2's operators → Week 2 Part 5 |
| Bridge, only when needed | Moving value between networks. Chains cannot natively see each other | Source chain + destination chain + the bridge mechanism → Week 2 Part 5 |
| DEX | Swapping assets through contracts, from your own wallet, no account | Your wallet + the DEX contracts + each token's contract → Week 3 |
| DeFi protocol | Depositing into a lending market or pool — finance by programs, not institutions | All the above + this protocol's contracts + its oracle + its economic design → Week 3 |
| Explorer / Dune | A block explorer or dashboard lets you observe and analyse on-chain activity; it is not the destination of the assets | The explorer's record; Dune's indexing and definitions if you use its dashboard → Part 7, Week 4 |
Bridges deserve early attention
Bridges have historically been a major source of large crypto exploits — worth understanding even before you know how they work.
The thing to actually take from this
Read the trust column downward and notice the shape.
| Stage | Trusting |
|---|---|
| Exchange | The exchange |
| USDC | Exchange + issuer |
| Self-custody | Yourself + issuer |
| Chain / L2 | The network; if using an L2, also its additional operators/controls |
| Bridge | Two chains + bridge mechanism |
| DEX | Wallet + several sets of contracts |
| DeFi protocol | All of the above + oracle + economic design |
Trust assumptions change as you move through the stack. They can increase, decrease or shift depending on the path. In this example, each extra component adds another assumption.
Moving to self-custody did not remove trust — it moved it onto you, and onto the software you interact with. Each additional protocol adds assumptions rather than removing them.
The single most useful sentence in Week 1
Web3 does not eliminate trust. It changes and redistributes trust assumptions.
Week 2 Part 6 turns this into a tool you can apply to anything.
Transaction lifecycle: how a blockchain actually runs
The journey above followed one user's choices. Now follow the machine underneath those choices. This is a generic model: different chains use different rules, but the same broad questions keep appearing.
| Stage | What happens in this generic model | Week 1 connection |
|---|---|---|
| Create and sign | A user describes an action, and a wallet authorises it with the account's key | Part 6 |
| Propagate and check | The request travels to network participants, which reject requests that do not follow the chain's basic rules | Part 7 |
| Propose a block | A chain-specific proposer or block producer chooses valid transactions for a candidate block | Part 3 |
| Verify and agree | Other participants check the block and its result; consensus determines which valid history the network follows | Part 2 · Part 3 |
| Update and read | Once accepted, the shared state includes the result. Wallets, explorers and applications can query it | Part 2 |
Week 1 pieces now connected
Part 2 explains the shared record. Part 3 explains how participants choose the accepted history. Part 4 explains why some participants do the work. Part 6 explains who can authorise an action, and Part 7 lets you watch one transaction make the journey.
A separate question: who is paid?
Depending on the chain's design, miners, validators or other block producers may receive protocol rewards and/or transaction fees. The amount and mechanism are chain-specific; payment is an incentive for participating, not part of the definition of every block.
This is the system-level view to keep: an instruction is authorised, carried through the network, checked, included under the chain's rules, and reflected in shared state. The details of how a chain selects and finalises blocks are what Part 3 examines.
Landscape
- On-ramp / off-ramp — converting between fiat and crypto in either direction. The service handling the conversion adds its own fees, limits and custody risk
- Layer 2 — a network such as Base that handles activity separately while relying on a base chain such as Ethereum for important settlement or security (Week 2). It adds another system and therefore another set of trust assumptions
- Wrapped asset — a token representing an asset from elsewhere (Part 5). Its value depends on the mechanism that links it to the underlying asset
- Slippage — the gap between the price you expected on a swap and the one you got. Thin liquidity or a large trade can make the gap wider
- Liquidity pool — pooled assets a DEX trades against (Week 3). More liquidity usually makes larger trades easier to execute without moving the price as much
- Oracle — a service supplying external data to contracts (Week 3). If the data is wrong or manipulated, the contract can make a wrong decision
- Yield — return from lending or providing liquidity. It is compensation for a risk; the useful question is which risk pays it
Worked example
The same journey as a decision rather than a diagram.
A student in Singapore wants to send S$500 to a family member abroad and has heard stablecoins are faster.
| They do | They gain | They take on |
|---|---|---|
| Buy USDC on a licensed exchange | A dollar value that can move quickly | Exchange custody; issuer reserves |
| Withdraw to their own wallet | They control custody; token-level issuer controls may remain | Full responsibility for keys |
| Send to the recipient's address | Can settle quickly, with low on-chain fees on some networks | Wrong address means it is gone. No reversal |
| Recipient converts to local currency | Done | Their local exchange, their local rules |
It can be faster or cheaper than four correspondent banks, depending on the network, on/off ramps and conversion route. It also has no error correction anywhere in the chain, several new counterparties, and two jurisdictions' regulations — Week 0 Part 5.
Whether that trade is worth making depends entirely on the situation
Noticing that it is a trade — rather than a straightforward upgrade — is what this week was for.
Further exploration — optional, not assessed
- ethereum.org — Layer 2 — a preview of Week 2
- ethereum.org — Decentralized finance — a preview of Week 3
- ethereum.org — Bridges — including a frank treatment of the risks
Sources and attribution
- ethereum.org — Stablecoins — Reuse (CC BY 4.0), adapted
- ethereum.org — Decentralized finance (DeFi) — Reuse (CC BY 4.0), adapted
- ethereum.org — Bridges — Reuse (CC BY 4.0), adapted
- ethereum.org — Layer 2 — Reuse (CC BY 4.0), adapted
- Web3 Internship Handbook — Reuse (permission granted); lifecycle structure used as inspiration and rewritten for this handbook
- Base documentation — Link, referenced for the L2 example
Named products are illustrative, not recommendations. Nothing here is financial advice.
Changelog
ff0f4-feat(academy): finalize Foundation learning experienceon57062-docs(foundation): strengthen beginner concept-to-reality progressionon8fbd1-docs(foundation): bridge core concepts and collaborationona931f-docs(foundation): finalize beginner learning path and handbook UXon2d4b4-docs(curriculum): finalize Week 0-2 Foundation revisionona15e4-docs(curriculum): add Week 0-2 drafting area and lesson contenton