What is HTML?
HTML is a set of rules for the configuration of the display and the content of a website. Essentially, it is not a programming language, but a poperty description language of the components of a web page. Using specific tags commands are given on how to manage an html documents content and how to show it in the users web browser, the program that we use to showcase different web pages.
Indicatively, the orders / tags of HTML, may:Import links into a Webpage
Import pictures into a Webpage
Formulate the text in bold or italic letters etc.
To create an html file, a plain text file is enough, which will have an .Html or .Htm suffix and this file will contain the desired commands with their appropriate parameters.
HTML can be written directly as code (source code) or can be automatically generated from a web design application the moment the creator, in GUI, simply use the various tools which the application provides to design the webpage (there are many available open source applications that you can download and install into your machine) .
For the correct writing of HTML there are web standards (https://www.w3.org/), which others take them into consideration and others not. An easy way to check web standards for a website is through the following validator: https://validator.w3.org/