AJAX is an acronym for Asynchronous JavaScript and XML. It’s a type of web programming technique that allows you to send and retrieve data from the server without refreshing the whole page.
This means that users can interact with your website or app while it communicates in the background, providing them with content they might not otherwise see if they had to reload a new page each time.
For example, when creating a shopping cart on most e-commerce websites, all items are added as soon as they’re selected because this interaction happens via “synchronous” pages where every click loads additional content either on top of what was there before or replacing it altogether (i.e., adding another layer).
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Origins of AJAX
Before the inception of AJAX, web pages functioned in a way that required full refreshing every time a request was made for new data from the server. This inefficiency resulted in sluggish website performance and an unsatisfactory user experience.
In response to these challenges, AJAX emerged as a solution for improved web functionality, with the term being coined in 2005 by Jesse James Garrett.
Through the implementation of AJAX, web developers were able to significantly improve the performance of web pages by enabling the server to send data only as needed, without requiring the entire page to reload every time a new request was made. This allows web pages to load faster and respond more seamlessly to user interactions, leading to a highly optimized and efficient user experience.
The development of AJAX has had an enormous impact on web design and development, enabling developers to create highly responsive, interactive, and dynamic web applications that are capable of providing users with seamless, engaging experiences.
AJAX Examples
const xhr = new XMLHttpRequest();
xhr.open('GET', 'https://example.com/api/data');
xhr.onreadystatechange = function() {
if(xhr.readyState === XMLHttpRequest.DONE && xhr.status === 200) {
const data = JSON.parse(xhr.responseText);
console.log(data);
}
};
xhr.send();
const xhr = new XMLHttpRequest();
xhr.open('POST', 'https://example.com/api/data');
xhr.setRequestHeader('Content-Type', 'application/json');
xhr.onreadystatechange = function() {
if(xhr.readyState === XMLHttpRequest.DONE && xhr.status === 200) {
console.log('Data sent successfully');
}
};
const data = {name: 'John', age: 30};
xhr.send(JSON.stringify(data));
$('form').submit(function(event) {
event.preventDefault();
const formData = $(this).serialize();
$.ajax({
url: 'https://example.com/api/data',
type: 'POST',
data: formData,
success: function(response) {
console.log(response);
}
});
});
Benefits of Using AJAX in Web Development
AJAX has many benefits, including:
- Improved user experience – web pages are able to update content without reloading the page for every interaction. This gives users a better experience on the site and also helps developers because it is faster than having to reload the entire webpage over again in order to see updates made by other changes they may have made to their code.
- Reduced bandwidth requirements when displaying dynamic data – since AJAX doesn’t require you to load up an entirely new webpage each time (instead of loading just certain elements), your server can handle more requests per second with less strain put onto its resources. It’s important that your website stays fast while being easy to use so people will keep coming back!
- Increased flexibility – developers can dynamically add new content to web pages without having to refresh the whole page. For example, if a user is viewing their inbox and they see an error message about not being able to send an email, clicking on that link could take them directly into your “reset password” form while preserving what was already visible in the original window – rather than reloading the entire webpage which would make things like scrolling through messages disappear.
- Improved usability for site visitors – AJAX enables website administrators to provide more interactive features by removing some of the frustrations associated with traditional static websites. The end result? Site visitors spend less time waiting for pages or images to load!
AJAX vs JSON
AJAX and JSON are two different languages, they are not really comparable since they serve different purposes, but they are often used together in web development. AJAX is a technique for dynamically updating web pages by exchanging data with a web server without requiring a full page refresh, while JSON is a lightweight data interchange format that is often used for transmitting data between a web server and a client.
Here are some key differences between AJAX and JSON:
AJAX:
- Stands for Asynchronous JavaScript and XML
- Is a technique for making asynchronous HTTP requests from a web page to a web server
- Can be used to update a part of a web page without refreshing the entire page
- Requires a client-side script to make the request and handle the response
- Can use various data formats for the response, such as JSON, XML, or HTML
- Is typically implemented using JavaScript and XMLHttpRequest (XHR) objects
JSON:
- Stands for JavaScript Object Notation
- Is a lightweight data-interchange format that is easy for humans to read and write and easy for machines to parse and generate
- Is often used for transmitting data between a web server and a client
- Supports simple data types like strings, numbers, booleans, and null, as well as complex data structures like arrays and objects
- Can be used with various programming languages, not just JavaScript
- Is not dependent on AJAX, but is often used with AJAX because of its simplicity and ease of use.
In summary, AJAX and JSON are not mutually exclusive, but rather complementary technologies that can work together to create dynamic and interactive web applications. AJAX is a technique for making asynchronous HTTP requests from a web page to a web server, while JSON is a lightweight data format that can be used to transmit data between a web server and a client.
