According to this criterion we can classify electronic certificates primarily into two:

• Certificates of Physical Person. They are the ones that incorporate the identity of a physical subject or citizen. It is aimed at citizens (i.e. physical third parties) and are mainly intended for personal procedures although, in certain circumstances, they can be used in the professional sphere.
• Certificates of Legal person. They incorporate a legal identity. Its use is intended for all kinds of organizations, whether they are companies, administrations or other types of organizations, all with a legal identity.
• Certificates of entity without legal personality. They bind their subscriber with signature verification data and confirm their identity to be used only in communications and data transmissions by electronic, computerised and telematic means in the tax field.

According to this criterion we find multiple Certificates, which are some of those offered by the different certification service providers:

• Server Certificate
• Certificate of belonging to a company
• Certificate of representative
• Certificate of seizure
• Company Stamp Certificate
• Electronic Invoice Certificate
• Certificate of Collegiate
• Etc.

According to this criterion, we can classify electronic certificates into two categories:

• Software certificates

  An Electronic Certificate is a digital document that can be stored on a USB memory, on a computer (in the certificate store) or on the hard drive. That Certificate is known as software certificate.

• Hardware certificates

  A certificate may also be stored in a cryptographic card, which is a card that incorporates an electronic chip. A clear example of a cryptographic card is the Electronic ID. On these cards it is possible to store one or more electronic certificates, which is known as hardware certification.

Chapter II of Law 11/2007 on Citizens' Electronic Access to Public Services establishes the forms of identification and authentication that can be used for the identification of the Administration and the administrative action. See Digital Identity for more information on identification and authentication concepts.

The following electronic certificates are derived from those sections of the Act and its implementing regulations.

• Electronic Headquarters Certificate

  The Headquarters certificate is a server certificate which identifies and authenticates the server as the Electronic Headquarters of a Public Administration.

  Electronic sites, where necessary, shall be provided with systems enabling the establishment of safe communications. In addition, they will use signature systems based on safe or medium device certificates to identify and maintain safe communication.

• Electronic Stamp Certificate

  According to the Law, it is the certificate used for the identification and authentication of the exercise of competence in automated administrative action.

  This means that the Electronic Seal is the one to be used for all administrative formalities carried out by telematic means, both for the identification of servers and the signing of electronic documents, and for the establishment of secure communications between machines.

• Certificate of Public Employee

  These are the certificates that each Public Administration can provide to its personnel for the identification and authentication of the exercise of the competence of the Public Administration.

  They jointly identify the incumbent of the post or post and the Administration or body in which he/she provides his/her services.