Know who you are communicating.
Digital IDs are digital identities used for securing various communicative functions. Think about signing emails (S/MIME), Microsoft Office documents and other electronic documents where you want to ensure integrity.
With a digital identity you can protects your email traffic for phishing attacks. The recipient of your email knows that it's really coming from you. Moreover, it gives the possibility, if both the sender and receiver have a digital identity, to send the message encrypted on a secure connection. Therefore, the message can't be intercepted.
The possibility of signing electronic documents means that you can use a digital ID to a Microsoft Office document like Word, Excel and PowerPoint as well. This verifies the authorship. A digital ID can be used to create an authentication system within an application, server or network as well. For instance, web servers as Apache and IIS offer the possibility to authenticate users by using a digital ID (client certificate).
An inexpensive ID that can be issued immediately after a validation email, when the identity assurance is not required. This is suitable to secure email and Microsoft Office documents. PersonalSign 1 is issued to email@example.com.
Can be used by individuals and is issued to firstname.lastname@example.org. The ID is personal validated and will only be issued if the applicant has proven his identity. The PersonalSign 2 allows them to authenticate to online services and digitally sign Office documents. Also email can be secured (S/MIME). The trust level is higher than with 1.
Is used for individuals representing organisations and is only issued to email@example.com. Your identity and the company existence is verified. The Pro version can secure emails, the identity can be verified with online services and Microsoft Office documents can be digitally signed by the company.
Has the same features as Pro, except that this concerned a department within a company. The ID is issued to firstname.lastname@example.org after the department and the company are validated.