jQuery is not defined error occurs when browser can't connect to jQuery library. Error affects approximately 78% of websites on the internet. Error can potentially shut down website to visitors
jQuery 3.7.1 comes in compressed and uncompressed versions. Slim build excludes ajax and effects modules. Source map files available for debugging but not required for users
Sends data to server using HTTP POST request. Added in jQuery 1.0. Returns jqXHR object as success callback
Stores arbitrary data associated with DOM elements. Added in jQuery 1.2.3. Allows setting multiple values for single element. Cannot be used on object, applet or embed elements. Returns jQuery object when called without parameters
jQuery provides controlgroup widget for horizontal navigation. Checkboxradio widget enables checkbox functionality. Button widget triggers datepicker display
jQuery click button triggers click events or adds functions to be called. Click event occurs when mouse button is pressed and released over element. Click method activates onclick function or triggers click event