jQuery Getting Started Questions and Answers: Several common beginner questions compiled_Basic knowledge

This section does not cover how to write jQuery, but only solves a few common questions for everyone, because these are also some questions that are often encountered in interviews. If you master jQuery, it can become a capital to increase your salary.
Friends who are new to jQuery will basically ask the same question, "What is jQuery?" and other similar questions. Understanding this question will promote subsequent learning. The following are some frequently asked questions that I have compiled :
1. What is jQuery?
2. What is a class library?
3. What is the relationship between jQuery and JavaScript?
4. What is the relationship between JavaScript and java?
5. What are JavaScript, jQuery, Ajax, Json, etc.? What's the difference?
I believe that many people have a vague feeling about these technologies and do not understand them very well. The above questions are definitely questions that beginners will have, if you are interested in it or want to control it. Then please follow KwooShung and march towards jQuery! let's GO!
Q: What is jQuery?
A:jQuery is a JavaScript class library. It was created by John Resig (American) and has attracted many JavaScript masters from all over the world to join the team.
Q: What is a class library?
A: This is a basic concept in the program. The so-called class can be understood as a collection of statements used to describe a group of objects with common attributes and functions. Literal understanding means that a class library is a collection of classes. Java and .net class libraries have similar meanings. But in jQuery, it is just a collection of many methods and functions, allowing us to achieve complex effects with simple code.
Q: What is the relationship between jQuery and JavaScript?
A: jQuery is written in JavaScript, which means that JavaScript can be called arbitrarily, but other programs cannot call it easily. It's like JavaScript is a chicken, jQuery is an egg, and chickens can only lay eggs. To put it more clearly, jQuery is written in JavaScript, just like eggs are laid by chickens.
If you still don’t understand, let’s take a look at another example:
We can compare JavaScript to text. If we use text to write two cookbooks, "A Complete Collection of Western Food Recipes" and "A Complete Collection of Chinese Food Recipes," the former is prototype ( Before jQuery, it was also a class library) and the latter was jQuery. The recipes contain a lot of cooking methods, which can also be called a class library of dishes. In the program, they are called class libraries, method libraries, function libraries, etc.
Q: What is the relationship between JavaScript and Java?
A: At first glance, they appear to be related or products of the same company. In fact, they are neither siblings nor developed by the same company. The former was developed by Netscape and the latter by Sun. Development, on April 20, 2009, Oracle announced that it would acquire Sun for US$7.4 billion. (You can search online for detailed information)
Q: What are JavaScript, jQuery, Ajax, Json, etc.? What's the difference?
A: After reading this, I think there is no need to talk about JS and jQuery anymore, right? If you still think you need to explain, then you will definitely understand after reading the previous questions and get to the point directly.
Ajax: The full name is "Asynchronous JavaScript and XML" (asynchronous JavaScript and XML). It is a combination of four technologies: JavaScript CSS DOM XMLHttpRequest, and JS is the core of Ajax. jQuery makes Ajax implementation easier and easier. Ajax is what we often call partial refresh.
JSON (JavaScript Object Notation) is a lightweight data exchange format. It is easy for humans to read and write but also easy for machines to parse and generate. It is based on a subset of JavaScript. Json uses a completely language-independent text format and can be simply understood as a format or exchange method for data storage.