Definitions:

1. It involves attaching or inserting new material after the original content without altering or replacing what is already present. VERB
   • When drafting the document, I realized I needed to add more information by appending and additional section.
2. The act of adding something, typically additional information or content, to the end of an existing document, file, list, or dataset. VERB
   • The researcher is appending the latest experimental data to the end of the report before submitting it for publication.

Synonyms:

• adding
• adding on
• attaching