Signature
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TLDR: A signature in computing is a data marker used to verify the integrity, authenticity, or identity of digital content, systems, or processes. It ensures that data has not been tampered with and is recognized by the system or application. Common types of signatures include cryptographic signatures for security, filesystem signatures for disk partitioning, and method signatures in programming languages to define function behavior.
https://en.wikipedia.org/wiki/Digital_signature
In partitioning, a signature like the one in the MBR (Master Boot Record) is a two-byte identifier (0x55AA) at the end of the first 512 bytes of a storage device. This signature validates the MBR as a bootable record recognized by the system firmware. Similarly, filesystems often include unique signatures to identify the disk format, ensuring compatibility during disk mounting and disk access operations.
https://www.kernel.org/doc/html/latest/filesystems/index.html
In security, cryptographic signatures ensure the authenticity of data or software. These signatures, generated using asymmetric encryption algorithms like RSA or ECDSA, verify that the content originates from a trusted source and has not been altered. For example, signed firmware or signed kernels rely on these signatures to pass checks like Secure Boot, protecting systems from unauthorized modifications. By ensuring authenticity and integrity, signatures play a vital role across computing disciplines.
https://www.nist.gov/itl/special-publications/nist-special-publication-800-107
- Snippet from Wikipedia: Signature
A signature (; from Latin: signare, "to sign") is a depiction of someone's name, nickname, or even a simple "X" or other mark that a person writes on documents as a proof of identity and intent. Signatures are often, but not always, handwritten or stylized. The writer of a signature is a signatory or signer. Similar to a handwritten signature, a signature work describes the work as readily identifying its creator. A signature may be confused with an autograph, which is chiefly an artistic signature. This can lead to confusion when people have both an autograph and signature and as such some people in the public eye keep their signatures private whilst fully publishing their autograph.