First, let's take a look at what HTML is.
HTML stands for HyperText Markup Language. It may sound complicated at first glance, but it's not. In fact, HyperText is just plain text, but it contains references to other text/resources/content. This term was brought to the web from literature. Open any book – its content is HyperText, as it contains references to other pages.
Now let's define what a «markup language» is. First of all, all websites are just pages with text, pictures, and links - this is exactly what HTML is. If you imagine website development as building a house, you first need a drawing (plan) to understand what will be located where - a window, a door, a living room, etc. The role of HTML is to serve as a blueprint for a website. Only later it will be decided what the walls will be like and what the doors and windows will look like.
You can see HTML markup on every page on the Internet. To do this, you need to go to the page, right-click, and select «View source» or «View page source» in the drop-down menu ( in different browsers the name of the item may be slightly different).
An HTML document opened in an editor is displayed as a regular text file; however, if an HTML document is opened in a browser, it is displayed according to the markup tags and is called a web page. One of the main tasks of any browser is to read an HTML document and display it as a web page.
HTML is not a programming language, which is why it only describes what is in a document (text, links, images, videos) using special words called tags. Tags are enclosed in angle brackets «<» and «>» and are most often used in pairs. First comes the opening tag, then its content, and then the closing tag. The closing tag is formed by adding a slash «/» before the tag name. Tags can also have attributes that expand their capabilities. It is always necessary to write attributes inside the opening tag.
Now let's look at the structure of a simple HTML page.
An HTML page starts with the <! DOCTYPE html> tag, This is the tag that tells the browser what version of the HTML language the page is using. Following the <! DOCTYPE html> tag there is a paired <html> tag. The HTML structure is often compared to a tree, while the <html> tag is its trunk or its cornerstone. Then this «trunk» is divided into two branches <head> and <body>. The <head> tag contains the necessary information for the browser and search engines, as well as styles for the visual design of pages. For example, in the tag, you should write the mandatory tag which is displayed on the browser tab. All text, graphics, and other code that is shown directly on the page should be inside the tag.
Doctype, HTML, Head, Title, and Body are mandatory tags and must always be written for a new page and in this order. All this is written in a file with the «.html» extension.
Now let's discuss the single and paired tags. Single tags in HTML do not have any content and are used only to create some graphic elements on the page. The closing tag is not used for single tags.
There are 16 single tags in HTML:
| <!doctype> | <input> |
| <area> | <keygen> |
| <base> | <link> |
| <br> | <meta> |
| <col> | <param> |
| <embed> | <source> |
| <hr> | <track> |
| <img> | <wbr> |
Paired tags are called so because they consist of two tags: an opening tag and a closing tag (<html> </html>). The element starts with the opening tag and ends with the closing tag. The content of the element includes everything between the opening and closing tags. The content can be text and/or another HTML element.
It is important to test the HTML code, check it for validation errors on the website pages, and ensure that the website works in all browsers since this is a basic requirement for almost all web developers. If there are any errors after the testing, it is necessary to make appropriate changes to the code. There are many online tools that help to check that the HTML code generates the desired result and that the website works in a simplified mode. It is possible to go the traditional way and use Chrome Developer Tools, but there are plenty of other online tools that are easier to work with.
Below are six tools for testing HTML code in a browser:
1. CodePen
This online tool is more of an online community where developers use various front-end tools such as HTML, CSS, JavaScript, and many libraries to write code. The tool works as an online code editor in a browser. This makes it one of the most popular tools for checking HTML code, as well as one of the largest developer communities where you can learn a lot about HTML, CSS, web development in general, and code testing.
2. Using a text editor
This is one more way to run an HTML file. Working in a text editor offline, such as Sublime Text or Notepad++, you simply save the file with the .html extension and run it by double-clicking on it. By default, it is launched in the browser installed on your local computer. You can also go to the Settings section of your device and change the default browser to analyze the output in different browsers.
3. JSFiddle
JSFiddle is an online development community that is also a platform for testing HTML code online in a browser. It started as an application in 2009, but later gained immense popularity. JSFiddle is mainly used for testing JavaScript code online, but you can also test HTML, CSS, and code written with some other front-end libraries. It has its own online editor and displays the output at the same time. It is one of the best tools for working with JavaScript. The only drawback is that you have to click the «Run»АА button to refresh the preview pane.
4. JSBin
Many beginners find the JSFiddle interface difficult to work with. JSBin is an alternative to JSFiddle and is comparatively easier to use. It has two types of access: free and professional. Both types allow unlimited free testing of HTML, CSS, and JavaScript code in the browser, but there is a fixed number of JavaScript libraries that can be enabled. If you want to access additional features such as private shopping carts and asset hosting, you need to register a professional account.
5. Liveweave
Liveweave provides previews of HTML code in real time and it is one of the most beautiful and enjoyable tools to work with. The interface is very simple and intuitive due to the resizable panels. When typing code in the built-in editor, it constantly gives suggestions, which makes the work much easier. In addition, one can easily save the code to the cloud and even download it as a .zip file for further use. It also allows working with JavaScript libraries such as jQuery and has a separate line that can be used to track product feedback.
6. HTMLhouse
HTMLhouse is the most suitable option for those who only need to work with HTML. The interface is clean and minimal, without any extra features or support. It was designed exclusively for HTML. Users can publish HTML and share it publicly/privately. For each piece of code that is written, there is an option to share a link in case there is a need to forward it.
There is also a free service called W3C's Markup Validation Service, which allows users to search for validation errors on website pages. This service checks the specified data for errors and creates a report with a list of them and recommendations for correction.
In addition to the tools mentioned above, some other HTML resources, such as HTML Goodies, may be useful for beginners. There's also the option of working with Chrome developer tools. To do this, launch an HTML document in Google Chrome and right-click on the HTML element you want to check. After clicking «Check, one will get tools for running, analyzing, and even debugging the code.
However, the main disadvantage of all these tools is that they demonstrate how the code looks in only one browser. If there is a need to test in different browsers, all of them must be installed. However, this is not always possible. For example, if a tester works in a Mac environment, they cannot directly test in IE. One of the ways to test websites in different browsers is by using online cross-browser testing tools such as LambdaTest. It is known to be one of the most impressive cross-browser testing tools that helps test the cross-browser compatibility of the code. Test results are based on the results of more than 2,000 browsers. Therefore, it ensures the smooth operation of the code in different desktop and mobile browsers and prevents many problems.
In conclusion, HTML is designed to help the browser understand what elements a web page consists of as well as the meaning of these elements. HTML is quite simple and it will not be too difficult to understand its structure. Besides, to make sure that the code works as expected, it can be checked with the help of various tools that will facilitate testing and help in finding bugs.
