What does ⟨ -,- ⟩ mean in the context of category theory?

Question

The above brackets are from https://en.wikipedia.org/wiki/Product_(category_theory) under the equational definition. I have also seen this notation in a few textbooks, particularly Categories For The Working Mathematician on page 13, paragraph 2. I suppose that it just denotes a pair of objects under question (not categorical objects). But I have not found a real explanation.

Answer 1

The wikipedia article you linked actually gives the definition:

... The unique morphism $f$ is called the product of morphisms $f_1$ and $f_2$ and is denoted $\langle f_1, f_2\rangle$

Answer 2

It is the operation "to pair things" which in the case of the product yields the arrow that maps into the product by pairing the arrows together for each factor of the product.