SEO guides
SEO Basics
SEO (search engine optimization) is the practice of improving a website so that search engines can find, understand and show its pages for relevant s…
Learning Resources and Free Guides
Plain-English guides that answer the question first and then go deeper. Read them before you enrol, alongside a course, or on their own.
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SEO guides (24)
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SEO guides
Keyword Research
Keyword research is the process of finding the words and phrases people type into search engines, judging the intent and competition behind each one,…
SEO guides
Search Intent
Search intent is the goal behind a search query: what the person actually wants to know, find or do. It is usually grouped into informational, naviga…
SEO guides
On-Page SEO
On-page SEO is the work you do on an individual page to help search engines understand it and help people choose and use it. It covers the title tag,…
SEO guides
Technical SEO
Technical SEO is the work that makes a website easy for search engines to crawl, render and index, and comfortable for people to use. It covers robot…
SEO guides
Content SEO
Content SEO is the practice of planning, writing and maintaining pages so they answer what people search for more usefully than the alternatives. It …
More SEO guides: Internal Linking, Off-Page SEO, Local SEO, Semantic SEO, JavaScript SEO, Structured Data, SEO Audit, SEO Tools, Topical Authority, Topical Map Creation, Keyword Clustering, Content Gap Analysis, E-E-A-T in SEO, Entity SEO, AI Search Optimization, Generative Engine Optimization (GEO), Answer Engine Optimization (AEO), Query Fan-Out
Web development guides (16)
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Web development guides
HTML
HTML (HyperText Markup Language) is the standard language for structuring content on the web. It uses elements, written as tags, to tell the browser …
Web development guides
CSS
CSS (Cascading Style Sheets) is the language that controls how HTML looks: colours, fonts, spacing, layout and how a page adapts to different screens…
Web development guides
JavaScript
JavaScript is the programming language that makes web pages interactive. It runs in every modern browser, where it can read and change the page throu…
Web development guides
PHP
PHP is a server-side scripting language for building dynamic websites. When a browser requests a PHP page, the web server runs the code, which can re…
Web development guides
MySQL
MySQL is an open-source relational database management system. It stores data in tables of rows and columns, and you read and change that data with S…
Web development guides
WordPress
WordPress is a free, open-source content management system (CMS) written in PHP that stores content in a MySQL or MariaDB database. It lets you publi…
More web development guides: APIs, CSS Flexbox, CSS Grid, Responsive Web Design, JavaScript DOM, PHP OOP, PHP Sessions and Cookies, PHP Security, PHP MVC, Git and GitHub
Networking & security guides (11)
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Networking & security guides
Networking Basics
Computer networking is the practice of connecting devices so they can exchange data using shared rules called protocols. A network combines hardware …
Networking & security guides
OSI Model
The OSI (Open Systems Interconnection) model is a seven-layer reference framework that describes how data moves from an application on one device to …
Networking & security guides
TCP/IP
TCP/IP is the suite of protocols that runs the internet and almost every private network. IP (Internet Protocol) addresses and routes packets between…
Networking & security guides
Routing & Switching
Switching moves frames between devices on the same local network using MAC addresses, while routing moves packets between different networks using IP…
Networking & security guides
Linux
Linux runs most servers, cloud workloads, firewalls and network appliances, and nearly every security tool is built for it. Learning the Linux comman…
Networking & security guides
Network Security
Network security is the set of policies, technologies and practices that protect the confidentiality, integrity and availability of data as it moves …
More networking & security guides: Cybersecurity Basics, IP Addressing, Subnetting, DNS, Linux Commands
Programming guides (6)
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Programming guides
Python Basics
Python is a general-purpose, interpreted programming language known for readable syntax that uses indentation to mark blocks of code. You write instr…
Programming guides
Python OOP
Object-oriented programming (OOP) in Python is a way of organising code around objects that bundle data (attributes) with the functions that act on i…
Programming guides
Data Structures
A data structure is a way of organising data in memory so that particular operations, such as looking up, adding or removing items, are efficient. Co…
Programming guides
Algorithms
An algorithm is a finite, ordered set of unambiguous steps that turns an input into the correct output. A recipe, a route to a station and the code t…
Programming guides
SDLC
The software development life cycle (SDLC) is the structured process teams follow to plan, build, test, release and maintain software. It breaks the …
Programming guides
Debugging
Debugging is the process of finding the cause of a defect in a program and fixing it. A good debugging process is systematic: reproduce the problem, …