If you want to know more how limits are used in Я, I recommend you to check out Push it to the limit article.
Limit is a special object with an unique morphism to it. In Я limit is Product.
Colimit is a special object with an unique morphism from it. In Я colimit is Sum.
That’s why these operators look this way - they resemble diagrams above (lo/la):
`lo` : into a o -> into a oo -> into a (o `P` oo)
`la` : into a o -> into aa o -> into (a `S` aa) o