Internet, Web Browsing and Email
Internet, Web Browsing and Email tests URL structure, browser behaviour, search techniques, email fields, attachments, and safe communication.
Core ideas
- The internet is a network of networks; the web is a service on it. A URL identifies a resource: protocol://host:port/path?query#fragment.
- HTTP is unencrypted; HTTPS uses TLS. A padlock indicates HTTPS, not that the site is honest.
- DNS translates domain names to IP addresses. A browser caches pages, cookies, and history; private/incognito mode limits local history but does not hide activity from the ISP or school network.
- Search operators: “exact phrase”, site:, filetype:, -word, OR. Evaluate sources by author, date, evidence, and bias.
- Email fields: To (primary recipients), Cc (visible copy), Bcc (hidden copy). Reply goes to sender; Reply All goes to sender plus all recipients.
- Attachments should be scanned and size-checked; cloud links suit large files. Never open unexpected attachments.
- Netiquette: clear subject, concise message, no ALL CAPS, quote selectively, respect privacy.
Worked example
https://www.example.com:443/notice?date=2025#top. Protocol = https; host = www.example.com; port = 443 (default HTTPS, usually omitted); path = /notice; query = date=2025; fragment = top. Reasoning: read left to right; the query starts at ?, the fragment at #. The domain is example.com; www is a subdomain. Do not call the whole string the “domain name”.
Traps
Do not put all recipients in To when using Bcc for privacy. Do not assume deletion from inbox deletes it from the server or recipient. Do not treat HTTPS as a trust guarantee. Phishing URLs may use lookalike domains (paypa1.com). Do not click “unsubscribe” on obvious spam.