
Digital signatures work using a technical process known as cryptography. Every digital signature is unique to a single user, meaning that no one can have the same signature with another person. Using a digital signature, a person can sign their document before sending it, and the recipient will easily be able to confirm that the document belongs to the sender. There are many advantages that come with using a signature to protect online documents.
1. Authentication

First, the signature allows for signer authentication. This is the process of confirming that the document was indeed sent by the owner. As stated above, no signature is similar to another. This will eliminate the chances of forgery. It may also be used against a person who claims that they did not send a file if the file is actually embedded with the person's digital signature. It will also assure the recipient that they are receiving the document from the right person. Again, this reduces the chances of identity theft on the internet.
2. Data integrity

Second, digital signatures protect the integrity of data while it is being transferred from one user to another. Without a means of protection, files can easily be interfered with before they reach the recipient. This can have adverse effects on the sender, including the loss of important data. It also puts the users at risk of having their files tampered with or destroyed while in transit. Digital signatures prevent this by having a unique hidden code that is embedded onto every binary bit of the document. This means that no part of it can be altered by any other person other than the signer.
3. Repudiation

Digital signatures also help in curbing instances of repudiation. Repudiation, in this case, refers to the claim that a person did not send a certain document. Because no digital signature is similar to another, each signature can be used to identify a specific sender. If the document was meant to be binding, then the person will be precluded from denying that they were involved in that transaction. On the inverse, it can also be used as proof that a person did not send a document if their signature does not match that which is attached to the file.
4. Legal Uses

The above digital signature solutions have proven very useful in courts of law. The codes are used as evidence that a person owns a certain file. For this reason, many countries have now come up with laws that govern the use of digital signatures as evidence in court. Such rules also outline how to obtain the evidence legally, without infringing on a person's privacy. For example, the signature should be easy to verify, without needing any audit trails. This is because such trails are governed by an entirely different legal regime. Additionally, such proof should not require information from service providers. Service providers are separate legal bodies that are bound to preserve the confidential information they have on their clients.
Creating a signature

Seeing the importance of digital signatures, many companies are now coming up with free online signature services. Their aim is to help out those who want to understand how digital authentication works. Such services have also gone further to include online sites that provide free software to create digital signatures. Users can easily follow a few steps and come up with their own unique codes, to be used when sending files online.
E-signatures

Before creating a digital signature, it is important for users to know the distinction between digital signatures and e-signatures. E-signatures are marks that are made online, to mimic a person's physical signature on paper. E-signatures are physical marks as opposed to cryptic codes. The e-signature is placed onto the document and appears like an image. This kind of signature is simple, and not secure because it can easily be forged. It is therefore not admissible as irrefutable proof that a document was signed by the owner.
Procedure
- The very first step in creating a digital signature is finding a digital ID certificate. A digital ID is a unique form of identification that is used by an individual person or corporate online. This ID will be linked to all documents signed by that person online. Because there it is very important for each user to be verifiable, organizations such as the European Union have created a list of trusted digital ID providers. A client should choose from such Trusted Lists.
- Next, the user should find a document application that works with their digital ID service provider. The application will be used to open the document and append the signature.
- The user should then proceed to click on the Add Signature option that comes with free online signature services. The process should be enabled by the application's administrator.
- After that, a client should click on the prompt to apply the digital ID certificate and select the name of their digital ID provider, as mentioned above.
- They should then follow the prompts to affix their online certificate
- Next, the user will be required to click on the option for signing the document.
- Lastly, they will need to enter their PIN which helps in identifying the sender. The document is then ready for sending.
Public and private keys

Once this is done, the private key is used to sign that document. The signing process works like a mathematical problem that can only be solved in one direction. That way, only the corresponding public key can be used to unwrap the code used to encrypt the file. All private keys are matched with public keys. The crypto code is attached to the entire document or part of it, depending on the user's preference. Embedding the entire document takes more time, but it is vital if the user wants to protect all the transferred data.
Conclusion

It is advisable for senders to use both electronic signatures as well as digital signatures. That way, the physical mark will be visible at first glance, and the online one will be used for verification.