Hello World Program

Solidity serves as a contract-oriented, statically-typed, high-level programming language specifically crafted for developing smart contracts on the Ethereum blockchain platform. It seamlessly combines the capabilities of contemporary programming paradigms with the essential attributes of security and reliability necessary for blockchain-based solutions. By utilizing Solidity, developers can create decentralized applications (dApps) and implement self-executing contracts that automate processes, facilitate transactions, and manage data in a trustless, transparent, and immutable manner.

Key points:

Solidity possesses a static and strong typing system, where variable and function identifiers are predetermined with precise types.
Solidity adheres to object-oriented programming principles, offering classes, objects, and inheritance similar to other object-oriented languages.
Solidity's nature is case sensitive.
Solidity finds extensive application in implementing smart contracts on Ethereum and other blockchain platforms.
The .sol extension is commonly used to save Solidity files.

Solidity Compilation:

The SOLC compiler serves the purpose of converting high-level Solidity code into bytecode, which represents low-level code. This bytecode is subsequently transformed into opcodes that are executed on Ethereum Virtual Machines (EVM).

Furthermore, the Solidity compiler provides an Application Binary Interface (ABI) that acts as a communication bridge between applications and smart contracts. Other applications utilize the ABI to interact with deployed smart contracts.

Now, let's proceed with writing and compiling our "Hello World" program using Solidity.

Exercise Manual

Step 1: Write Hello World Smart Contract using Solidity and compile it with solc compiler.

Step 2: Create a new file named HelloWorld.sol. As you might have guessed, the file extension .sol is used for Solidity file.

Step 3: It is important to define the license for the Smart Contract Code. We have multiple options like MIT, Apache, GPL, LGPL etc. In this case, we are selecting MIT.

Step 4: Specify the version of the Solidity programming language for the code. In this case, we have defined that this code can work with any version newer than version 0.8.0 of Solidity.

Step 5: Begin the definition of a new contract called HelloWorld.

Step 6: Defines a function called sayHelloWorld. The function is public, which means it can be called by anyone. It is marked pure, which means it does not modify the state of the contract. The function returns a string value, which is specified as memory to indicate that the string is not stored permanently on the blockchain.

Step 7: Add code to return Hello World string when function sayHelloWorld() is called.

Step 8: Close the function definitions.

Step 9: Close the contract definitions.

Step 10: Open a terminal and navigate to the directory where you have saved the HelloWorld.sol file.

Step 11: For deployment, generally two things are required. Bytecode and ABI (Application Binary Interface).

Step 12: Bytecode is the low level code that actually runs on EVMs. Run solc command to generate the bytecode.

Step 13: ABI act as a bridge between applications and smart contract for interaction. Run solc command to generate ABI.

Step 14: So now we know how a Hello World contract is created and compiled.

Hello World Program in Solidity

Exercise Manual