Image metadata and GPS
Photos may include camera model, capture time, software, author fields, and GPS coordinates. Inspect the exact outgoing file, then create and verify a new copy when metadata is unnecessary.
Visible information matters too
Removing metadata does not hide faces, street signs, screens, documents, balances, tabs, or account IDs visible in the pixels. Crop or redact those separately.
PDF and archive review
PDFs and ZIP files can contain comments, attachments, hidden files, paths, form data, metadata, and underlying text. Use a trusted local workflow and verify the final artifact rather than trusting its appearance.
Integrity checks
A SHA-256 checksum can confirm that file bytes match a trusted published value. It does not prove that the publisher or file is safe.