Grammatically speaking, what significance is there for using the word “for” at the start of a sentence?

Question

I’ve seen this used somewhat uncommonly in literature and in posts on social media. It tends to happen, from my experience, when someone is trying to explain something in-depth or as a addendum to a point trying to be made. For example, and to create a circular reference:

I have a question about the usage of the word for, “For I’ve seen this used somewhat uncommonly in literature and in posts on social media.” Is there a term or any significance and/or difference for using the word “for” in the quoted sentence of the second paragraph of this question versus not using it in the first paragraph?

In: 0

Answer 1

“For” can be used to mean “because” here but it’s not common usage and kind of archaic.