Introducing solcjs
solcjs is a Node.js library and command-line tool that is used to compile solidity files. It doesn't use the solc command-line compiler; instead, it compiles purely using JavaScript, so it's much easier to install than solc.
Solc is the actual Solidity compiler. Solc is written in C++. The C++ code is compiled to JavaScript using emscripten. Every version of solc is compiled to JavaScript. At https://github.com/ethereum/solc-bin/tree/gh-pages/bin, you can find the JavaScript-based compilers of each solidity version. solcjs just uses one of these JavaScript-based compilers to compile the solidity source code. These JavaScript-based compilers can run in both browser and Node.js environments.
Note
The browser Solidity uses these JavaScript-based compilers to compile the Solidity source code.
Installing solcjs
solcjs is available as an npm package with the name solc. You can install the solcjs npm package locally or globally just like any other npm package. If this package is installed...
