> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/web/digital-signature/samples.md).
# Digital signature samples using JavaScript
Learn how to build a signing application with Sign App, request signatures, sign documents, and review signed documents. Explore the Full API for DigitalSignature to digitally sign and certify PDF doc
## Sign App - Repository
Demonstrates building a signing application where users can request signatures on documents by placing fields, signing documents, and reviewing signed documents.
GitHub Repository
## Code Samples
### [Sign and Certify - Digital Signature](/web/get-started/samples/digitalsignaturestest.md)
Demonstrates how to digitally sign a PDF and certify a PDF document.
### [Validate - Digital Signature](/web/get-started/samples/viewerdigitalsignaturevalidationtest.md)
Shows how PDFNetJS can be used to validate digital signatures in a document.
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