What are Lightning Web Components?
Lightning Web Components, or LWCs, are the Salesforce implementation of the new breed of lightweight frameworks built on existing web standards. LWCs leverage templates, custom elements, shadow DOM, modules, decorators and other new language constructs that are available in ECMAScript 7 and later.
LWCs are the ‘new’ method for creating Lightning Components in Salesforce. The previous or original method which is still supported, is called Aura or the Aura Component model.
For Salesforce Developers, this means a new way to build web applications that will in some instances replace the Model-View-Controller (MVC) paradigm associated with Visualforce and Apex.
When we are not building new apps from the ground up, we will leverage the ‘old’ method of creating Lightning Components: Aura.