On a sunny day, the day as usual, I was sitting in front of a computer screen staring at the tabs in an open browser. Every now and then I type something that is quite important, even though it's actually just a status update on Twitter or Facebook. Behind me, there were several S3 students who were having fun chatting and discussing. Suddenly a question came from one of the female students, "What's the difference between Twitter and Facebook?"
My mind then drifted, thinking of various kinds of explanations that I could use as an answer to that question. There are some crazy answers that appear, here are one.
There are some fundamental differences about Facebook and Twitter. One that may be quite significant is the difference in the relationship between each individual in the two social networking sites. On Facebook, social relations between two individuals are commutative. That is, if A is friends with B, surely B is also friends with A. Unlike Facebook, Twitter uses the following-follower system. Understanding the following is the people we follow the status update, while followers are the people who follow our status updates. In this system, if the A follow (follows) the B, then the B does not have to always follow the A. The B can choose whoever he wants to follow the status update.
To make this difference look simpler, let's use graph theory to represent social relations between members on this social networking site. Before starting a graph representation, let's discuss a little theory about graphs.
Graph theory is used to learn about graphs, namely a mathematical structure that is used to model pair relationships between objects in a particular set of objects. A graph is a set of nodes or vertices and a set of edges or arcs that connect two specific nodes. Many things in this world can be modeled with graphs. The PageRank algorithm in Google's search engine is one example of the application of graphs.
There are two types of graphs. The first type is called an undirected graph which does not consider the difference between two nodes connected by an edge. The second type is called directed graph (digraph), which means that the edge is directed from one node to another. Let's look at the representation of social relations on Facebook and Twitter to end all this madness 😀
Friendships in Facebook can be modeled using non-directed graphs. This is due to the existence of an equal relationship between two people on this site as previously explained. So if the A is connected with B, then B is also connected to the A (commutative nature). Graph representation of social relations in Facebook can be seen in the picture below.
Examples of graph representation of social relations on Facebook
In the picture above we can see, A has a friendship with B. B has a friendship with A, C, and D. C has a friendship with B and D. Finally, D has a friendship with B and C.
Unlike Facebook, social relationships on Twitter can be represented as directed graphs, or digraphs. First, we assume that the direction on the edge shows the flow of information (or status updates) from one account to another. This means that if A follows B, then A will get status information from B, so that there will be a directed edge from B to A. For more details, see the following picture.
Examples of representations of social relations on Twitter
From the picture above, we can see some social relationships. The A follows B, or in other words A is a follower of B. B is a follower of C and D. C is a follower D. And finally D is a follower of B. On the edge connecting between B and D is