Introduction: what this topic is and why it matters
Modern web development is built on a handful of recurring architectural ideas and a large bank of general-knowledge (GK) concepts. Government job exams (BCS, Bank IT-officer, various IT-cadre posts) love this area because a single MCQ can test whether you know what a CDN is, why the same-origin policy exists, or the difference between a web server and an application server. These are short, factual, high-yield questions.
This lesson stitches together the whole mixed web-GK bank into one place: the MVC design pattern, CORS / same-origin policy, web caching and CDNs, several classic "X vs Y" comparisons (web server vs application server, portal vs hosting, browser vs search engine, e-commerce vs m-commerce, cookies vs sessions vs storage), WordPress and CMS, a complex HTML table with rowspan/colspan, CSS frameworks, canvas vs SVG, and a secure PHP + MySQL login using prepared statements. Master this and you can answer almost any "web concepts" MCQ on sight.
Learning objectives
By the end of this lesson you will be able to:
- Explain the MVC pattern, draw its request flow, list its advantages, and name real frameworks (Laravel, Django, Spring).
- State the same-origin policy precisely and explain how CORS relaxes it.
- Distinguish the three layers of web caching (browser, proxy, CDN) and define a CDN.
- Compare web server vs application server, portal vs hosting, browser vs search engine, and e-commerce vs m-commerce.
- Choose correctly between cookies, sessions, localStorage and sessionStorage.
- Explain what a CMS is and why WordPress dominates.
- Build a complex HTML table using
rowspanandcolspan, and read one under exam pressure. - Name common CSS frameworks and contrast canvas vs SVG.
- Write a SQL-injection-safe PHP login with prepared statements.