Article: How Many Triangles can You See?

An interesting article sent to all staff from A Kumar 27/6/2017. I came to the conclusion there were 18 Triangles! Almost wishing I taught a math class to give them this as a first up task. What I really appreciated about this article was that they provided an insight (through diagrams) of how they figured out there were 25-26. Here's the link to the article.