Help Center

Plain guides to using AI assistants correctly and safely in everyday work.

• How to use AIHow to ask AI chat assistants good questions, with example prompts, limitations and privacy.
• Creating images with AIImage generation tools, writing a good image prompt and what to watch for in commercial use.
• Creating video with AIGenerating video from text and from images, typical uses, limitations and ethical notes.
• AI for writing codeIn-editor completion, chat and terminal agents; tips for safe and efficient use.
• AI tools that make your work easierIdeas for using AI in emails, meeting notes, presentations, spreadsheets, translation and summaries.

Recognise phishing emails, protect your accounts with two-factor authentication and strong passwords, and keep backups against ransomware.

• How to spot a phishing emailThe tell-tale signs of fake emails, how to check links and attachments, and what to do if you clicked.
• What is two-factor authentication and how do you turn it on?Add a second layer of security to your accounts: verification methods and the general route for Google and Microsoft accounts.
• How to create a strong password. What is a password manager?Long passwords that are never reused, passphrases, and how to use a password manager.
• What is ransomware? The 3-2-1 backup ruleHow to protect yourself against ransomware, the 3-2-1 backup rule and what to do during an attack.
• What is SSL? What does SSL do on a website and in email?What https and the padlock on a website and the SSL setting in an email program protect, and how they differ.

Defence guides for site owners and developers: SQL injection, XSS, CSRF, file uploads, sessions, security headers, backups and incident response.

• Website security guide: where should you start?Threat types, layered defence, priorities and a roadmap to all the security guides.
• What is SQL injection and how do you prevent it?Prepared statements, allowlists, a least-privilege database user and hiding error messages.
• What is XSS and how do you prevent it?Context-aware output escaping, Content-Security-Policy, HttpOnly cookies and rich-text sanitising.
• What is CSRF and how do you prevent it?CSRF tokens, SameSite cookies, Origin checks and using POST for state-changing actions.
• File upload security and web shellsSecure upload rules, disabling execution in the upload folder, signs of a web shell and what to do if you find one.
• Login and session securityPassword hashing, attempt limits, session fixation, cookie flags and authorisation checks on every request.
• Security headers and HTTPSHSTS, CSP, X-Content-Type-Options, Referrer-Policy and Permissions-Policy, with an .htaccess example.
• DDoS and bot attacksSigns, CDN and WAF, rate limiting, caching and working together with your hosting provider.
• Software updates and plugin securityKeeping the CMS, plugins, themes and libraries up to date; removing what is unused; supply chain risk.
• Server and hosting securitySFTP/FTPS, file permissions, directory listing, error display, sensitive files and database access.
• Website backup and monitoringFile and database backups, restore drills, file integrity, logs and uptime monitoring.
• What to do if your website is hackedStep-by-step incident response: maintenance mode, evidence, passwords, clean-up, entry point, restore and notifications.
• WordPress securityUpdates, few and trusted plugins, administrator accounts, wp-config protection, XML-RPC and login limits.
• Website security checklistWeekly, monthly and yearly tasks; every item links to the relevant guide, and the list is printable.

Plain guides to calibration certificates, calibration intervals, measurement uncertainty and keeping track of your measuring equipment.

• How to read a calibration certificateWhat the identification, traceability, measurement results, uncertainty and accreditation details on a certificate mean.
• How to determine a calibration intervalFixed intervals versus methods based on past data, the factors that affect the interval, and record keeping.
• What is measurement uncertainty?Type A and Type B uncertainty, combined and expanded uncertainty, k=2 and a simple worked example.
• How to keep an equipment calibration tracking listInventory fields, reminders, using the records at audits, and when to move from Excel to software.

Plain guides to Nginx, proxies and reverse proxies, HTTPS, load balancing, caching, CDNs and common server errors.

• What is Nginx and what is it used for?The roles of Nginx, its event-driven architecture, how it differs from Apache, configuration blocks and basic commands.
• What is a proxy server?Forward proxy versus reverse proxy, typical uses, a comparison with VPNs and what to know about privacy.
• What is a reverse proxy?What a reverse proxy does, typical architectures, the real visitor IP and headers, how it relates to a CDN, and a short Nginx example.
• How to set up Nginx as a reverse proxyStep-by-step setup: server block, proxy_pass, forwarded headers, WebSocket, timeouts and real client IP.
• HTTPS in Nginx: setting up an SSL certificateGetting a certificate, redirecting to HTTPS, HSTS, SSL termination and automatic renewal in Nginx.
• What is load balancing?How requests are spread across several servers, the Nginx upstream settings, health checks and the session problem.
• Caching and compression in NginxHow to set up caching and compression in Nginx correctly with static file headers, gzip and proxy_cache.
• Nginx security settings: rate limiting, headers, access restrictionsRate limiting, security headers, hidden-file and admin-path restrictions, and request limits in Nginx.
• 502, 504 and other Nginx errors: causes and fixesWhat 502, 504, 413, 499, 403 and 404 mean, their likely causes, diagnosis from the logs and the fix.
• What is a CDN (content delivery network)?What a CDN is, how it is put in place, and what to watch for with real IPs, caching and origin server security.
• Migrating from Apache and .htaccess to NginxSide-by-side examples, an equivalents table and a test list for moving .htaccess rules into the Nginx configuration.
• Nginx and PHP-FPM: how PHP sites run on Nginxfastcgi_pass, SCRIPT_FILENAME, try_files, the pool concept, socket permissions and the 502 error.
• What is a data centre and how do you choose one?What a data centre is, the service types on offer and what to weigh when choosing a provider: location, SLA, redundancy, backups and exit terms.