SOLID STATE PRESS
← Back to catalog
ERC-721 and NFTs Explained cover
Coming soon
Coming soon to Amazon
This title is in our publishing queue.
Browse available titles
Cryptocurrency & Blockchain

ERC-721 and NFTs Explained

Token Standards, Smart Contracts, and the Mechanics of Digital Ownership — A TLDR Primer

You've heard the term a hundred times — NFT — and you still aren't sure what it actually means. Is it the image? The code? The receipt? Most explanations either drown you in jargon or skip the parts that matter. This guide skips neither.

**ERC-721 and NFTs Explained** is a focused, 20-page primer covering exactly what non-fungible tokens are under the hood: how Ethereum's smart contracts create and enforce ownership, what the ERC-721 token standard actually requires a contract to do, and why a JPEG stored on a blockchain is fundamentally different from one sitting on your phone. If you've searched for a clear *blockchain NFT explained for students* resource and found only hype or whitepapers, this is the middle ground you were looking for.

The book walks through six tightly written sections: the meaning of fungibility, how smart contracts execute on Ethereum, every required function in the ERC-721 interface, how minting and metadata work (and why most NFT images live off-chain), how wallets and marketplaces interact with contracts, and an honest look at what NFTs can and can't actually do. This is an *ethereum token standards study guide* built for someone who wants to understand the mechanics, not just the headlines.

Ideal for high school and early college students taking courses in computer science, economics, or blockchain technology — and for anyone who wants to stop nodding along and start actually understanding.

Pick it up and read it in one sitting.

What you'll learn
  • Explain what makes a token 'non-fungible' and how that differs from ERC-20 tokens
  • Read and understand the core functions of the ERC-721 standard
  • Trace how minting, transferring, and ownership are recorded on Ethereum
  • Understand the role of metadata, tokenURI, and off-chain storage like IPFS
  • Evaluate common claims, misconceptions, and risks around NFTs
What's inside
  1. 1. What an NFT Actually Is
    Defines fungibility, distinguishes NFTs from cryptocurrencies, and clarifies what is and isn't stored on-chain.
  2. 2. Ethereum, Smart Contracts, and Token Standards
    Explains the platform NFTs live on: how Ethereum runs smart contracts and why standards like ERC-20 and ERC-721 exist.
  3. 3. Inside ERC-721: The Functions That Define an NFT
    Walks through the required functions and events of the ERC-721 interface and what each one actually does.
  4. 4. Minting, Metadata, and tokenURI
    Covers how new NFTs are created, how images and traits are linked to tokens, and why most NFT data lives off-chain.
  5. 5. Markets, Royalties, and Wallets
    Explains how marketplaces like OpenSea interact with ERC-721 contracts, how royalties work (and don't), and the role of wallets.
  6. 6. What NFTs Are Good For, and What They Aren't
    Neutral assessment of real use cases, limitations, and the technical and legal questions that remain open.
Published by Solid State Press
ERC-721 and NFTs Explained cover
TLDR STUDY GUIDES

ERC-721 and NFTs Explained

Token Standards, Smart Contracts, and the Mechanics of Digital Ownership — A TLDR Primer
Solid State Press

ERC-721 and NFTs Explained

Token Standards, Smart Contracts, and the Mechanics of Digital Ownership — A TLDR Primer

Copyright © 2026 Solid State Press.

Published by Solid State Press.

All rights reserved. No part of this book may be reproduced or transmitted in any form without prior written permission, except for brief quotations in critical reviews and educational use.

Part of the TLDR Study Guides series.

Contents

  1. 1 What an NFT Actually Is
  2. 2 Ethereum, Smart Contracts, and Token Standards
  3. 3 Inside ERC-721: The Functions That Define an NFT
  4. 4 Minting, Metadata, and tokenURI
  5. 5 Markets, Royalties, and Wallets
  6. 6 What NFTs Are Good For, and What They Aren't
Chapter 1

What an NFT Actually Is

A dollar bill and a Bitcoin have something in common: if you swap one for another identical unit, nothing has changed. You have the same value, the same utility, nothing lost. That property has a name — fungibility — and it is the single most important concept for understanding what an NFT is.

Fungible means interchangeable on a one-to-one basis. Every dollar in circulation is worth exactly every other dollar. Every unit of Ether (Ethereum's native currency) is worth every other unit of Ether. You would never say "I want this specific Ether, not that one" — they are identical by definition.

Non-fungible means the opposite: each unit is unique and not directly interchangeable with another. A concert ticket is non-fungible. Row 4, Seat 12 is a different thing from Row 20, Seat 3, even if both are "tickets to the same show." A signed first-edition book is non-fungible. Your passport is non-fungible — it has your name, your photo, a unique serial number. Swapping it with a stranger's passport does not leave you in an equivalent position.

An NFT — non-fungible token — is a record on a blockchain that is unique and distinguishable from every other record in the same collection. The word "token" here just means a unit of data that a blockchain treats as an asset you can own and transfer. Unlike one Ether, which is identical to any other Ether, each NFT has its own identity: a unique numeric ID that no other token in the same contract shares.

What "ownership" actually means on a blockchain

A blockchain is a public ledger — a list of records that many computers store simultaneously, making it extremely difficult to alter any entry after the fact. When someone says they "own" an NFT, what exists on that ledger is an entry stating, roughly: Token ID 4271 in Contract 0x…abc belongs to wallet address 0x…xyz. That entry is what ownership means in an NFT context. It is a row in a shared, tamper-resistant database.

About This Book

If you are a high school student who has heard the phrase "non-fungible token" and still cannot explain what it means, a developer curious about Ethereum token standards but intimidated by the technical documentation, or a parent trying to make sense of what your kid is buying online, this book is for you. It also works as a blockchain NFT explained for students crash course — no prior crypto experience required.

The book covers how NFTs work explained simply: what makes a token non-fungible, how an ERC-721 smart contract beginner guide reads in practice, what minting and metadata actually do, and what NFT digital ownership explained to teens actually means legally and technically. It doubles as an Ethereum token standards study guide and a what-is-an-NFT cryptocurrency primer rolled into one. Short by design, with no filler.

Read straight through first to get the full picture. Then work the examples in each section and attempt the problem set at the end to test yourself.

Keep reading

You've read the first half of Chapter 1. The complete book covers 6 chapters in roughly fifteen pages — readable in one sitting.

Coming soon to Amazon