Here is an excellent ressource for the jQuery how to and jQuery documentation.
This work is only in english for the moment, but it seems it's a good idea for anyone to translate.
Here is the contents...
Chapter 1: Welcome
Chapter 2: JavaScript Basics
Chapter 3: jQuery Basics
Chapter 4: jQuery Core
Chapter 5: Events
Chapter 6: Effects
Chapter 7: Ajax
Chapter 8: Plugins
Chapter 9: Performance Best Practices
Chapter 10: Code Organization
Chapter 11: Custom Events
The examples are very useful and well documented.
Example 1.1: An example of inline JavaScript
Example 1.2: An example of including external JavaScript
Example 1.3: Example of an example
Example 2.1: A simple variable declaration
Example 2.2: Whitespace has no meaning outside of quotation marks
Example 2.3: Parentheses indicate precedence
Example 2.4: Tabs enhance readability, but have no special meaning
Example 2.5: Concatenation
Example 2.6: Multiplication and division
Example 2.7: Incrementing and decrementing
Example 2.8: Addition vs. concatenation
Example 2.9: Forcing a string to act as a number
Example 2.10: Forcing a string to act as a number (using the unary-plus operator)
Example 2.11: Logical AND and OR operators
Example 2.12: Comparison operators
Example 2.13: Flow control
Example 2.14: Values that evaluate to true
Example 2.15: Values that evaluate to false
Example 2.16: The ternary operator
Example 2.17: A switch statement
Example 2.18: Loops
Example 2.19: A typical for loop
Example 2.20: A typical while loop
Example 2.21: A while loop with a combined conditional and incrementer
Example 2.22: A do-while loop
Example 2.23: Stopping a loop
Example 2.24: Skipping to the next iteration of a loop
Example 2.25: A simple array
Example 2.26: Accessing array items by index
Example 2.27: Testing the size of an array
Example 2.28: Changing the value of an array item
Example 2.29: Adding elements to an array
Example 2.30: Working with arrays
Example 2.31: Creating an "object literal"
Example 2.32: Function Declaration
Example 2.33: Named Function Expression
Example 2.34: A simple function
Example 2.35: A function that returns a value
Example 2.36: A function that returns another function
Example 2.37: A self-executing anonymous function
Example 2.38: Passing an anonymous function as an argument
Example 2.39: Passing a named function as an argument
Example 2.40: Testing the type of various variables
Example 2.41: A function invoked using Function.call
Example 2.42: A function created using Function.bind
Example 2.43: A function being attached to an object at runtime
Example 2.44: Functions have access to variables defined in the same scope
Example 2.45: Code outside the scope in which a variable was defined does not have access to the variable
Example 2.46: Variables with the same name can exist in different scopes with different values
Example 2.47: Functions can "see" changes in variable values after the function is defined
Example 2.48: Scope insanity
Example 2.49: How to lock in the value of i?
Example 2.50: Locking in the value of i with a closure
Example 2.51: Using a closure to access inner and outer object instances simultaneously
Example 3.1: A $(document).ready() block
Example 3.2: Shorthand for $(document).ready()
Example 3.3: Passing a named function instead of an anonymous function
Example 3.4: Selecting elements by ID
Example 3.5: Selecting elements by class name
Example 3.6: Selecting elements by attribute
Example 3.7: Selecting elements by compound CSS selector
Example 3.8: Pseudo-selectors
Example 3.9: Testing whether a selection contains elements
Example 3.10: Storing selections in a variable
Example 3.11: Refining selections
Example 3.12: Using form-related pseduo-selectors
Example 3.13: Chaining
Example 3.14: Formatting chained code
Example 3.15: Restoring your original selection using $.fn.end
Example 3.16: The $.fn.html method used as a setter
Example 3.17: The html method used as a getter
Example 3.18: Getting CSS properties
Example 3.19: Setting CSS properties
Example 3.20: Working with classes
Example 3.21: Basic dimensions methods
Example 3.22: Setting attributes
Example 3.23: Getting attributes
Example 3.24: Moving around the DOM using traversal methods
Example 3.25: Iterating over a selection
Example 3.26: Changing the HTML of an element
Example 3.27: Moving elements using different approaches
Example 3.28: Making a copy of an element
Example 3.29: Creating new elements
Example 3.30: Creating a new element with an attribute object
Example 3.31: Getting a new element on to the page
Example 3.32: Creating and adding an element to the page at the same time
Example 3.33: Manipulating a single attribute
Example 3.34: Manipulating multiple attributes
Example 3.35: Using a function to determine an attribute's new value
Example 4.1: Checking the type of an arbitrary value
Example 4.2: Storing and retrieving data related to an element
Example 4.3: Storing a relationship between elements using $.fn.data
Example 4.4: Putting jQuery into no-conflict mode
Example 4.5: Using the $ inside a self-executing anonymous function
Example 5.1: Event binding using a convenience method
Example 5.2: Event biding using the $.fn.bind method
Example 5.3: Event binding using the $.fn.bind method with data
Example 5.4: Switching handlers using the $.fn.one method
Example 5.5: Unbinding all click handlers on a selection
Example 5.6: Unbinding a particular click handler
Example 5.7: Namespacing events
Example 5.8: Binding Multiple Events
Example 6.1: A basic use of a built-in effect
Example 6.2: Setting the duration of an effect
Example 6.3: Augmenting jQuery.fx.speeds with custom speed definitions
Example 6.4: Running code when an animation is complete
Example 6.5: Run a callback even if there were no elements to animate
Example 6.6: Custom effects with $.fn.animate
Example 6.7: Per-property easing
Example 7.1: Using the core $.ajax method
Example 7.2: Using jQuery's Ajax convenience methods
Example 7.3: Using $.fn.load to populate an element
Example 7.4: Using $.fn.load to populate an element based on a selector
Example 7.5: Turning form data into a query string
Example 7.6: Creating an array of objects containing form data
Example 7.7: Using YQL and JSONP
Example 7.8: Setting up a loading indicator using Ajax Events
Example 8.1: Creating a plugin to add and remove a class on hover
Example 8.2: The Mike Alsup jQuery Plugin Development Pattern
Example 8.3: A simple, stateful plugin using the jQuery UI widget factory
Example 8.4: Passing options to a widget
Example 8.5: Setting default options for a widget
Example 8.6: Creating widget methods
Example 8.7: Calling methods on a plugin instance
Example 8.8: Responding when an option is set
Example 8.9: Providing callbacks for user extension
Example 8.10: Binding to widget events
Example 8.11: Adding a destroy method to a widget
Example 10.1: An object literal
Example 10.2: Using an object literal for a jQuery feature
Example 10.3: The module pattern
Example 10.4: Using the module pattern for a jQuery feature
Example 10.5: Using RequireJS: A simple example
Example 10.6: A simple JavaScript file with dependencies
Example 10.7: Defining a RequireJS module that has no dependencies
Example 10.8: Defining a RequireJS module with dependencies
Example 10.9: Defining a RequireJS module that returns a function
Enjoy the work of Rebecca at jQuery Fundamentals
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