Error correction tutorial

The Glottography tutorial series now includes a guide on error correction, showing how to update polygon geometries and metadata.

Add license information

This release adds license information (CC BY 4.0) to the repository.
No changes to tutorial content.

Initial public release of Glottography tutorials

This release archives the initial public version of the Glottography
tutorials as published on https://glottography.github.io/tutorials/.

It includes tutorials on:

• Georeferencing a language map
• Digitising language polygons
• Recording Attributes & Metadata
• Assigning Glottocodes
• Data Curation

The website should be considered the canonical, up-to-date version.