How to connect a DApp frontend to the Ethereum network?

Alright, no problem! Let's talk about this in plain language.

How to Connect a DApp Frontend to the Ethereum Network?

Imagine you're building an online store (that's your DApp frontend), but all your goods and money are stored in the world's largest, most secure, transparent vault (that's the Ethereum network). The question now is, how does your online store interact with this vault to allow customers to buy things with the money stored inside?

You can't just plug an ethernet cable directly into the "vault." You need an "intermediary" or a "standard process." This process mainly consists of three key parts:

1. The User's "Digital Wallet" (e.g., MetaMask) - Like a Customer's "ID Card + Bank Card"

This is probably the most crucial component. When a user visits your DApp website, they usually have a plugin like MetaMask (the 'little fox' wallet) installed in their browser.

You can think of this wallet as the user's "ID card" and "bank card" in the blockchain world. It serves two core functions:

• Proof of Identity: When the user clicks the "Connect Wallet" button on your website, the wallet tells your site: "Hello, I am the owner of this address (e.g., 0x123...abc), this is my identity." This way, your website knows who has arrived.
• Transaction Authorization: When a user wants to buy something, your website cannot directly take money from their wallet. Your website needs to prepare a "payment request" and then send it to the user's wallet via code. The wallet will pop up, clearly telling the user: "This website wants you to pay XX Ether, do you agree?" Only after the user personally clicks "Confirm" in their wallet can this transaction occur.

In summary: The wallet is the most important security barrier and authorization tool between the user and your DApp.