Module 3: Software and Applications
Updates and versions
🏠The everyday picture
A car manufacturer discovers a fault in the brakes and recalls the cars to fix it free. Owners who skip the recall keep driving with faulty brakes. Software updates are recalls that arrive over the internet.
📘What it really is
- Updates fix bugs, close security holes and sometimes add features.
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Security updates are the most important. Most successful attacks use holes that were already fixed in an update the victim didn't install.
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Software uses version numbers, often in the form
MAJOR.MINOR.PATCH, like22.11.0: - PATCH (22.11.0 → 22.11.1): small fixes, safe to install;
- MINOR (22.11 → 22.12): new features, nothing should break;
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MAJOR (22 → 23): big changes that may break things built for the old version. This is called semantic versioning. You'll see it everywhere in development.
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LTS (Long-Term Support) versions get fixes for years. For anything important, prefer LTS.
🖱️Try it
Check for updates for your OS and your browser, and install them. Then find your browser's version number (Chrome: Settings → About Chrome) and identify the major version.
✅Quick check
A tool goes from version 4.2.1 to 4.2.2. Is it likely to break your project?
Show the answer
Unlikely. A patch change should only contain fixes.
Why do servers usually run LTS versions of software?
Show the answer
They get security fixes for a long time without big changes that could break the running website.