Try these two great sites to reference syntax reference, especially HTML:
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Use when creating a website or _________________________________________________________________________________________________________________
When parsing data from the website
Understand how attributes of html tags have attributes, nesting, data , how tags are nested within each other using HTML Tree Generator
Understand how images are stored and referenced in the html
Work with navigating the tags for Beautiful Soup or or front end development development
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Chrome Add-ons
- BuiltWith Technology Profiler - Use this to scan what tech a website is using
- JSON Viewer Awesome - Use this to format json to make it more readable