This paper will describe the XML initiative in which the author is involved, and explore the current trends of metadata. Metadata is becoming very important in the context of the world wide web. The most common definition of metadata is "data about other data". No standard has been established for the metadata yet, but the Dublin Core Metadata Initiative (DCMI) is working to establish an international cross-disciplinary consensus. Other metadata initiatives have been taken place to establish standards for web metadata and metadata interchange.
The gigantic flow of information cannot be successfully processed and retrieved without the indexing effort. Creators of web pages must now provide the content analysis of the data to help search engines to improve relevance and precision.