Social Network Analysis, SNA, does not necessarily have to do with the current concept of online "social networks" (such as Facebook, Instagram), but with the social relationship of different people with each other. The definition of SNA is "the process of investigating social structures through the use of networks and graph theory". In simplified terms, SNA can be represented by a graph of "who knows whom", with as many levels as necessary, to see the relationships between people. 

Tools such as Sentinel Visualizer show the relationships between targets and third parties.

SNA is related to the "6 degrees of separation" theory, which postulates that anyone on Earth can be connected to anyone else through a chain of no more than five intermediaries. In other words, it only takes six connections, or "degrees", at most to connect any two people, regardless of their geographic location or social status. 

SNA networks start from a person of interest and add nodes. At the first level (or "first degree of separation") are those known directly to that person. At the second level, those known to his or her acquaintances, etc. These networks make it possible to visualise connections between groups of people, which may not be obvious at first glance. 

Having these relationships can be useful to know in advance what the flow of information will be in each group or how networks or sets of people are usually created in that relationship graph (also called "sociogram"). And that opens the door to multiple civilian and military uses, especially in today's highly connected online world, where it is much easier to follow the relationships between people based on their social networks (this time we are referring to Facebook, X, LinkedIn and the rest).

The role of online social networks in SNA 

In a hyper-connected world, social networks such as Facebook or X, with their Like functions and connections between users, are an excellent source of information to apply SNA techniques and, starting from a central individual, to know his or her immediate and secondary relationships. The immediacy and timeliness of this information is of great value, as SNA graphs can be updated almost in real time to reflect the current state of connections and find out where concentrations occur at certain nodes, giving clues about who are the important people in that group, network or organisation.

Because of its ubiquitous presence, access to this information is very simple and does not require complex tools or hardware. Conventional Internet access and a PC or laptop may be sufficient to perform relatively complex analyses. On the other hand, if the right utilities are available, SNA analysis can be expanded beyond the conventional web to the Deep Web or the Dark Web, which are much more widely used by actors involved in subversive activities or who must remain out of the public eye. 

 Applications of SNA 

 We would like to give a brief overview of the possible uses of SNA applications. Businesses, marketing, public health, education, and many other sectors benefit from the information that can be extracted from an SNA diagram, applied to a given group of people. When used with organisations, rather than individuals, SNA can be of great help in the business and corporate environment by allowing the tracking of non-obvious logistical chains or inter-firm relationships. 

1. Corporate Strategy and Organizational Design 

In business environments, SNA can reveal informal communication channels, map internal collaboration, and uncover knowledge bottlenecks. This is particularly valuable in large organizations where traditional org charts fail to reflect actual working relationships. SNA can identify hidden influencers, improve knowledge sharing, and help restructure teams for greater efficiency. 

2. Marketing and Customer Analytics 

In digital marketing, SNA helps identify key opinion leaders and influencers within a customer base. Understanding who influences purchasing decisions, how word-of-mouth spreads, and how tightly consumer communities are connected enables more targeted and cost-effective campaigns. 

3. Public Health and Epidemiology 

During health crises, such as pandemics, SNA can be used to trace transmission pathways, understand how communities interact, and design interventions that focus on high-risk hubs. It also aids in behavioral health studies, addiction recovery networks, and community outreach planning. 

4. Education and Academic Research 

In education, SNA is used to assess collaborative learning and peer interactions. In research, it maps the collaboration between scholars or institutions, identifying leading contributors in specific fields or emerging interdisciplinary trends. 

5. Political Science and Civic Engagement 

SNA supports the analysis of grassroots movements, political polarization, and civic participation. By analyzing discourse on social platforms or public forums, it becomes possible to identify influential voices, assess the spread of ideologies, or evaluate public sentiment in real time. 

 SNA AND ARTIFICIAL INTELLIGENCE 

Although the mechanism of social network analysis does not use artificial intelligence systems per se, as it only collects connections between targets and represents them visually, the amount of information this process generates can quickly escalate to a point where it is virtually impossible for a human to analyse all the relationships. 

 This is why many SNA systems use AI models to summarise results or find patterns that may not be obvious at first glance. Combined with NLP systems we have already mentioned, and facial or object analysis platforms, this expands the analysis possibilities not only to text, but also to images.

ETHICAL CONSIDERATIONS  

The power of SNA also comes with serious ethical responsibilities. Because it often involves personal or sensitive data, its use must comply with privacy regulations, data protection laws, and ethical guidelines for surveillance and behavioral profiling. 

Transparency, informed consent, anonymization techniques, and secure data handling are essential to maintain trust and uphold rights while still benefiting from the insights SNA can offer.