Comprehensive Study of What Are Digital Signatures and How They Ensure Authenticity in the Digital Realm

Over the course of many years, if you've ever put a thought on what is a digital signature, we have the solution you might be searching for. Digital signatures have become an increasingly popular method for signing documents. Unlike a traditional signature, a digital signature uses advanced cryptographic techniques to ensure the document's authenticity.

In this article, we'll talk about different things related to digital signatures. We will learn about digital signature certificates and how they are legally accepted, and we will also introduce a tool called UPDF. This tool lets you use electronic signatures instead of digital ones if you like.

Part 1. What is a Digital Signature?

A digital signature is like a special code that helps check if a document is real and if it has been changed. It tells us who signed the document and if they agreed to what is written in it. But it is really good for companies because it keeps documents safe, saves time, and lowers expenses. When a document has a digital signature, it's hard for someone to fake or change it later.

Moreover, it also ensures that the person signing the document is authentic. Using digital signatures makes things faster because you do not have to waste time printing or mailing documents. You can keep track of documents efficiently and make the work go smoothly.

Moreover, the amount of money you save is up to the mark. Signing digitally means you don't have to spend on printing, mailing, or keeping paper files. So, using digital signatures helps keep things more secure, faster, and less expensive for businesses and people.

Part 2. What is a Digital Signature Certificate?

A digital signature certificate is like a special electronic ID card that's similar to a driver's license or passport, but it is all done using computers instead of physical papers. It serves as proof of your identity in the digital world. Just as you show your physical documents to prove who you are, a DSC can be presented online to verify your identity. This, in return, helps you access various internet services.

It is especially useful for digitally signing documents or accessing restricted information securely. Digital signature certificates offer a higher level of security compared to traditional signatures. They provide strong evidence about the origin, status, and identity of electronic documents, messages, or transactions. Also, in many countries, digital signatures hold the same legal power as signatures by hand.

Additionally, the certificate for digital signatures can be used for any message, regardless of whether it's coded or not. It combines the public key with an identity, ensuring it belongs to a specific person or entity. This verification process adds an extra layer of trust and security to digital transactions.

Part 3. Is a Digital Signature Legally Binding?

Digital signatures, which are a type of electronic signature, are surely legally binding. They use complex algorithms and certificate authorities to verify the signer's identity and ensure the document's integrity. Meanwhile, different countries have established laws to ensure the enforceability of electronic signatures.

In the United States, the United States Electronic Signatures in Global and NCA (E-Sign Act) and the UETA govern electronic signatures. But in the United Kingdom, the Electronic Communications Act of 2000 and the Electronic Signatures Regulations Act of 2002 recognize that electronic signatures are valid.

Moreover, in Australia, electronic signatures hold the same legal standing as traditional wet ink signatures under the ETA of 1999 and ETR of 2000. In addition, the European Union replaced the e-signature Directive in 2016 with Regulation (EU) No 910/2014, also known as eIDAS. However, refer to the list below to learn more about countries where digital signatures are legal:

  • Argentina
  • Austria
  • Belgium
  • Brazil
  • Bulgaria
  • Chile
  • Colombia
  • Costa Rica
  • Croatia
  • Cyprus
  • Czech Republic
  • Denmark
  • Dominican Republic
  • Ecuador
  • Estonia
  • Finland
  • France
  • Germany
  • Greece
  • Guatemala
  • Hong Kong
  • Hungary
  • India
  • Ireland
  • Italy
  • Jamaica
  • Japan
  • Latvia
  • Liechtenstein
  • Lithuania
  • Luxembourg
  • Malaysia
  • Malta
  • Mauritius
  • Mexico
  • Montenegro
  • Netherlands
  • Norway
  • Pakistan
  • Panama
  • Peru
  • Philippines
  • Portugal
  • Republika Srpska
  • Romania
  • Russia
  • Scotland
  • Singapore
  • Spain
  • Sweden
  • Switzerland
  • Slovakia
  • South Africa
  • South Korea
  • Turkey
  • Ukraine
  • Uruguay
  • Venezuela
  • Wales

Part 4. How to Add a Digital Signature to PDF

Adobe Acrobat can be a reliable tool for comprehensively adding a digital signature to a PDF document. This PDF software lets you view, create, edit, and manage PDF files. It offers a user-friendly interface and robust features for working with digital signatures. To add a digital signature using Adobe Acrobat, first, ensure you have a digital ID or certificate.

This digital ID serves as your unique identifier and helps establish the authenticity of your digital signature. You can obtain a digital ID from a trusted certificate authority or create one using Adobe Acrobat. For better clarification, follow the steps introduced below:

Step 1: Open your document in Adobe Acrobat and select "Use a Certificate" from the left side. On the following screen, tap "Digitally Sign" and use the mouse to click and drag the area where you want the signature to appear.

Step 2: After selecting the area, configure the ID you want to use by tapping "Configure Digital ID." Click "Create a new Digital ID" on the following window and press "Continue."

Step 3: The next thing you need to decide is where you want to store the new digital ID. You can either store it in your file or in the Windows Certificate Store.

Step 4: Next, you are required to provide details like your name, organization where you work, country, email, and others. Once you have provided all the details, tap "Continue." Now, create a password for your digital ID on the following screen that you will need to use when digitally signing any document using this digital ID.

Step 5: Select your created digital ID and add the password you set for this. Afterward, select the signature appearance style and enable the “Lock document after signing” option if you don’t want anyone to change the document information. To complete this digital sign process, click the “Sign” button and save your document on the system with the signature.

Part 5. How to Add an Electronic Signature to PDF if You Don't Want Digital Signature

As a user, if you have been looking long for a simple way to add an electronic signature to your PDF documents, look no further than UPDF. This PDF toolkit is a comprehensive tool designed specifically for working with PDF files. It provides a range of features for your PDF documents. Moreover, it ensures that the format and quality of your PDF files remain intact throughout the process.

Supports Windows 7 or later100% secure

Supports macOS 10.14.6 or later100% secure

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Moreover, you won't need any specialized skills or experience to use it. UPDF lets you quickly type or draw your signature directly onto the PDF document. With that, UPDF allows you to create up to 4 signatures, giving you flexibility in your signing options. You can enter your signature using your keyboard, trackpad, or mouse, whichever is more comfortable for you.

Additionally, UPDF lets you customize your signature line by adjusting its style to make it bolder or more prominent. You can even choose the color of your signature to suit your preferences.

Main Key Features of this Productive Tool

  • Protect videos with watermarks.
  • Customize headers and footers as desired.
  • Crop unwanted parts from specific pages.
  • Split and extract pages easily.
  • Enhance readability with reader mode.
  • Effortlessly annotate documents with no obstacles.
  • Relaxing dark mode for nighttime work.

Simplified Steps to Add Electronic Signatures Quickly with UPDF

Here, we will guide you regarding the steps to add electronic signatures if needed. So, follow the instructions mentioned below:

Step 1: Launch UPDF on Your Computer

To begin, download and install UPDF on your computer. Once the installation is complete, launch the UPDF software. When the UPDF interface appears, locate, and click the "Open File" button. You can import the PDF document you want to use. After choosing the PDF file you want from your computer, press the "Open" button. Once the PDF file is imported successfully, you will see it shown on the UPDF interface.

Step 2: Accessing the Signature Feature in UPDF

To add your signature to the PDF document, navigate to the "Comment" icon on the left. Clicking on this icon will open a set of comment-related options. Among these options, locate and click on the "Signature" icon at the top of the comment panel. This will activate the signature feature within UPDF.

Step 3: Create a Signature Using Different Methods

UPDF offers three options for creating your signature, keyboard and mouse. Choose the method that suits you best. After creating your signature using one of the available methods, it's time to apply and adjust it within the PDF document.

create signature

Step 4: Adjust Your Signature for Final Preview

UPDF allows you to place your signature at the desired location within the PDF. Move the signature to the appropriate position by clicking and dragging it. You can also resize or rotate the signature if necessary, using the available options within UPDF. Take your time to adjust the signature until you are satisfied with its placement and appearance.

Supports Windows 7 or later100% secure

Supports macOS 10.14.6 or later100% secure

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Part 6. FAQs on Digital Signature

1. What is a digital signature in cryptography?

A digital signature in cryptography is a unique electronic stamp that ensures the authenticity and integrity of digital documents or messages. It involves using mathematical algorithms to create a digital document fingerprint, which is then encrypted using the signer's private key.

Anyone with access to the signer's public key can verify this encrypted signature. Confirming that the document has not been tampered with and was indeed signed by the authorized individual.

2. What is a digital signature in e-commerce?

When buying things online, a special mark is used to check if they are real and safe. This mark helps verify the identity of the people involved and ensures that the information shared between them remains secure and unchanged.

3. What are the three NIST-approved digital signature algorithms?

The NIST, which is a government organization, has given its approval to various ways of creating digital signatures. Three popular ones are RSA, widely used for digital signatures and encryption. It is based on the difficulty of factoring large composite numbers into their prime factors.

Next, DSA is a FIPS for generating and verifying digital signatures. This uses math stuff called modular exponentiation and discrete logarithms. Also, ECDSA is a different version of DSA that works with something called an elliptic curve. It provides the same level of security as DSA but with shorter key sizes, making it more efficient for resource-constrained devices.

4. What is a digital signature in cybersecurity?

In cybersecurity, a digital signature is crucial for ensuring the authenticity and integrity of digital communications, documents, and transactions. It helps verify the sender's identity, detect tampering or modifications, and establish trust between the parties involved. When we use special codes, digital signatures make things extra safe to stop bad people from getting in.


Summing up, if “what digital signature is” has been your query for a long, we have discussed it now. It is a secure and reliable way to sign electronic documents. These tools use unique methods to ensure the paper is real and hasn't been messed with. Digital signatures are legally binding and accepted in many countries worldwide. They provide a higher level of security compared to traditional signatures.

However, to add an electronic signature to your PDF documents, you can use the UPDF PDF editor. Using the UPDF tool, you can efficiently add electronic signatures to your PDFs and enhance your document management experience. It simplifies the process and ensures that your signatures are securely applied to your files.

Supports Windows 7 or later100% secure

Supports macOS 10.14.6 or later100% secure

100% secure

100% secure