What is a browser cache? How it speeds up websitesWhere your browser stores copies of images, scripts and fonts, why cached pages load faster, and how to clear the cache or force a fresh copy.What is a CDN? A plain explanationWhy web pages load fast everywhere: how content delivery networks cache files at the edge, route visitors to the nearest server, and protect sites from attacks.What is HTTP/3? A plain explanationThe newest version of HTTP runs on QUIC, a transport built on UDP instead of TCP. Here's what changes — and why pages feel faster with it.What is caching? Browser, CDN, server, and database caching explainedHow caching works at every layer of the web — browser cache, CDN edge cache, server-side cache, and database cache — and when each one matters for speed and scalability.What is code splitting? How it works and when to use itCode splitting divides a JavaScript bundle into smaller chunks that load on demand, speeding up initial page load. This guide explains the technique, the tools, and when it matters most.What is a database transaction? ACID properties explainedA database transaction bundles several operations into one all-or-nothing unit. This guide explains transactions, the ACID properties (atomicity, consistency, isolation, durability), and isolation levels.What is Server-Side Rendering (SSR)? How it works and when to use itServer-side rendering generates the full HTML for a page on the server in response to a request — delivering a complete, crawlable page to the browser. Here's how SSR works, how it compares to client-side rendering, and when it makes sense for your project.What is WebAssembly (WASM)? How it works and when to use itWebAssembly is a binary instruction format for a stack-based virtual machine — a portable compilation target that lets you run C, C++, Rust, and other compiled languages in the browser and beyond. Here's how it works and when it's worth using.What are Core Web Vitals? LCP, INP, and CLS explainedCore Web Vitals are a set of Google metrics that measure the real-user experience of a web page: loading, interactivity, and visual stability. Learn what LCP, INP, and CLS measure, their target thresholds, and how to improve them.How to optimize images for the web: formats, resizing, lazy loading, and CLSImages are usually the heaviest assets on a page. Here's how to pick the right format, serve the right size, lazy-load what's offscreen, and stop images from shifting your layout.What is a database index? How database indexes work and when to use themA database index is a data structure that lets a database find rows without scanning the whole table, usually a balanced tree (B-tree) ordered by the indexed columns. It makes equality, range, sort and join queries fast, at the cost of write overhead and storage. This guide explains how indexes work, clustered vs non-clustered, and when (and when not) to create one.What is load balancing? How load balancers work and key algorithmsLoad balancing is the process of distributing incoming traffic across multiple servers so that no single server is overloaded. A load balancer sits in front of a pool of servers and decides where to send each request, trading total capacity for reliability and speed. This guide explains how load balancers work, the difference between Layer 4 and Layer 7, the main routing algorithms, and how to choose one.Web compression: how gzip and Brotli shrink the webWhen a browser loads a page, the HTML, CSS and JavaScript are usually sent compressed. Here's how gzip and Brotli work, and why Brotli often wins for text.What is lazy loading? How deferring resources speeds up the webLazy loading is a performance strategy that defers non-critical resources (images, iframes, JavaScript, CSS) until they are needed. Learn what can be lazy-loaded, the native loading attribute, the Intersection Observer API, and when lazy loading helps or hurts. 