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Software Development101 guidesLinux64 guidesLinux Kernel24 guidesWordpress14 guidesAndroid9 guidesDeveloper Tools9 guides

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Install Chrome on Ubuntu—and Know Who Updates ItguideWho Is Really Logged In to This Linux Machine?guideMake Room in Windows Without Deleting What MattersguideLet the Linux tree Command Explain a DirectoryguideResume Large File Transfers over Unstable SSHguideLaunch a Secure Amazon EC2 Instance Step by Stepguide

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Linux, OS Concepts and Networking

List Files Installed by a Linux Package

Use the package database for installed ownership, repository content indexes for packages not installed, and archive queries for downloaded DEB/RPM files. These inventories describe packaged paths—not every file created later by services, scripts, or users.

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System Administration, Security

Fix Apache “ErrorDocument” 404 Failures

The message means Apache could not serve the original request and then failed again while handling that error. Test the custom error URI as an ordinary request, trace the selected virtual host and mapping, fix authorization or rewrites, and verify the final response remains 404.

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Website Hosting

Register and Secure a Domain Name Properly

Registering a domain creates a contractual, renewable right to use a name; it does not buy the name forever. Put the correct person or organization in control, calculate renewal risk, secure the registrar account, and document DNS and recovery before launching.

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Website Hosting

Verify Namecheap Promo Codes and Real Renewal Costs

A coupon is useful only when it applies to the exact product, account, term, and checkout date. Use Namecheap’s live offer details, verify the cart before payment, and compare renewal-inclusive cost instead of choosing a service by the first-year headline.

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Search Engine Optimisation ( SEO )

Create Custom Meta Descriptions in Osclass

Osclass already provides a site description and a `meta_description_filter` extension point. Use a plugin to choose concise page-specific text, leave escaping to one known output boundary, and verify the rendered canonical pages instead of editing core files.

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Search Engine Optimisation ( SEO )

Audit and Fix Overlong HTML Title Tags

An overlong `<title>` is a review signal, not an automatic SEO defect. Crawl the rendered canonical pages, find missing, duplicated, verbose, and templated titles, then rewrite the high-impact cases around intent and verify what search engines recrawl.

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Wordpress

Show Subcategories on WordPress Category Archives

On a category archive, WordPress already knows which term is being viewed. Read that queried term, fetch its direct children with `get_terms()`, and render escaped term links—without hard-coding IDs into a fragile copied template.

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Android Applications

Read Android API Level and Build Information Safely

Android’s `Build` and `Build.VERSION` APIs expose platform and firmware metadata, but those values serve different purposes. Use the numeric API level for compatibility checks, treat display strings as diagnostics, and avoid turning hardware fields into tracking identifiers.

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Web Design and Development

Add a Google Map and Marker to a Contact Page

A useful contact map does more than draw a pin. This implementation uses Google Maps JavaScript API’s current advanced marker, restricts the browser key, keeps the address usable without JavaScript, and avoids the blank-map mistakes that waste an afternoon.

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