レッスン 1
What Is XML? 日本語ガイド
日本語の xml what is xml ガイド: Understand XML structure and common developer use cases.
このコンテンツはまだ日本語で用意されていません。ローカライズが完了するまで English 版を表示しています。
XML (Extensible Markup Language) describes structured data with nested elements, optional attributes, and human-readable tags. Unlike JSON's braces, XML uses opening and closing tags:
<project>
<artifactId>demo-app</artifactId>
</project>
Where developers still meet XML
- Maven / Gradle POM files for Java builds
- Android manifests and resource XML
- SVG vector graphics embedded in apps or docs
- Sitemaps, RSS/Atom feeds, and legacy enterprise configs
JSON and YAML dominate new APIs, but XML remains entrenched in mobile, Java, and publishing pipelines.
Well-formed vs valid
- Well-formed — tags match, attributes are quoted, one root element. Parsers require this.
- Valid (optional) — conforms to a schema such as XSD. Many day-to-day tools only check well-formed syntax.
DevCove's formatter focuses on well-formed XML you can prettify, validate, and minify locally.
Key takeaway
XML is a text envelope for structured data. The next lessons cover namespaces, Maven/Android patterns, and how to debug parse failures quickly.