Introducing WebAssembly
In this section, we will look at how WebAssembly works. One way of running Blazor is by using WebAssembly, but for now, let’s focus on what WebAssembly is.
WebAssembly is a binary instruction format that is compiled and, therefore, smaller. It is designed for native speeds, which means that when it comes to speed, it is closer to C++ than it is to JavaScript. When loading JavaScript, the JavaScript files (or inline) are downloaded, parsed, optimized, and JIT-compiled; most of those steps are not needed for WebAssembly.
WebAssembly has a very strict security model that protects users from buggy or malicious code. It runs within a sandbox and cannot escape that sandbox without going through the appropriate APIs. Suppose you want to communicate outside WebAssembly, for example, by changing the Document Object Model (DOM) or downloading a file from the web. In that case, you will need to do that with JavaScript interop (more on that later, and don...
