Back to topics

What can a digital signature actually prove?

A digitally signed message may be readable by anyone while still allowing checks on its origin and whether it changed. Those checks depend on the keys and the trust placed in them; they do not make the message's claims true.

4–5 min

Questions you could explore

  • How do signing and verification use different keys?
  • What changes if the signing key is compromised?

Start reading

Ready to try your ideas aloud?

Your topic carries over. Record up to 2½ minutes, depending on your plan.

Computers and AI

Why can a damaged QR code still work?

A scratch or stain does not always stop a QR code from being read. Its stored information includes redundancy, but that does not mean any part of the image can be covered without consequence.

3–5 min
Computers and AI

How does a website name become an internet address?

You remember a website by its name, while the network needs an address for the connection. DNS supplies that translation, sometimes from a saved answer and sometimes by asking other servers.

4–5 min
Computers and AI

Same emoji, different picture

The same emoji can arrive with a different expression or style from the one you saw when sending it. Unicode identifies characters and sequences, while software platforms choose artwork and decide what their versions support.

2–3 min
What can a digital signature actually prove? | Speech Topic | speaking.app