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Website security & health, explained.

Short, practical guides to the things AstraScope checks — what each issue means, why it matters, and exactly how to fix it. No jargon for its own sake.

Security· Beginner

The security headers every site should send

HSTS, X-Content-Type-Options, Referrer-Policy, frame protection and Permissions-Policy — what each response header does and how to set it.

2 min read
Security· Intermediate

A practical guide to Content-Security-Policy

CSP is the strongest defence against cross-site scripting. Learn what it controls, how to roll it out safely with report-only, and how to avoid unsafe-inline.

2 min read
Accessibility· Beginner

Alt text that actually helps

Alternative text is how images work for screen-reader users and when images fail to load. Learn the difference between decorative and informative images, with examples.

1 min read
SEO· Beginner

Canonical URLs and duplicate content

One page can be reachable at many URLs. Canonical tags tell search engines which one counts — done wrong, they quietly bury your pages.

2 min read
Security· Beginner

HTTPS, TLS and mixed content explained

Why every site needs HTTPS, what TLS versions to support, how mixed content undermines a padlock, and where HSTS fits in.

1 min read
Security· Intermediate

Securing cookies: HttpOnly, Secure and SameSite

Three cookie attributes stop most session-theft and cross-site request attacks. Learn what each does and how to set them.

1 min read
SEO· Beginner

Titles and meta descriptions that earn clicks

The title tag and meta description are your listing in search results. Learn how to write ones that rank and get clicked, and the mistakes that waste them.

1 min read
SEO· Beginner

robots.txt and sitemaps, done right

robots.txt controls crawling; a sitemap advertises your URLs; noindex controls indexing. Mixing them up hides pages by accident.

1 min read
SEO· Beginner

Finding and fixing broken links

Broken links frustrate visitors, waste crawl budget, and leak ranking signals into dead ends. Here's how they happen and how to clear them.

1 min read
Performance· Beginner

Faster images: formats, sizing and lazy loading

Images are usually the heaviest thing on a page. Modern formats, correct dimensions and lazy loading cut weight and stop layout jumping.

1 min read
Performance· Intermediate

Core Web Vitals: LCP, CLS and INP

Google's three user-experience metrics measure loading, visual stability and responsiveness. Learn what each means, the thresholds, and how to improve them.

1 min read