jQuery

• use a CDN (content delivery network) to load but drop it in PRIOR to your custom js.
• jQuery selectors utilize CSS selector notation to query elements
• data- attribute, just like setAttribute, can create unique data values for developers to use
  • id and class are for designers. data- is for developers to add more meta-data to tags
• jQuery can only add a listener on an element that currently exists and will NOT update ones created after
• EVENT DELEGATION -> add a listener to a parent object and have THAT listen for the children to have their events triggered
  • $('ul li).on('click', callback) becomes `$('ul').on('click', 'li', callback)
  • $('parent').on('event', 'child', callback)
• Ajax -> runs queries on the internet
  • $.ajax('http://google.com') => gets data from google
  • $.ajax('path/to/file') => local path
  • $.ajax('/filepath', {method: "GET", dataType: "JSON}).then(data => //do the thing)