How the web works: HTTP, cookies, formats, tooling
How the browser and server talk: request, response, headers
Open topicGET, POST and others; what 200, 404, 403, 500 mean
Open topicWhat an address is made of and how ?key=value works
Open topicA page is an HTML tree you can read in full
Open topicHow a form becomes a request: GET vs POST, the body
Open topicJSON: structure and data types
Open topicURL-encoding, base64, hex - encoding is not encryption
Open topicWhat runs in the browser vs on the server - and why it matters
Open topicHow a site remembers you between requests
Open topicLogin, sessions and tokens: how a site recognizes you
Open topicElements, Network, Application, Console - the recon toolkit
Open topicRequests from the command line
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