A connective is a word or phrase that links clauses or sentences. Connectives can be conjunctions (eg but, when, because) or connecting adverbs (eg however, then, therefore).

Are they called connectives or conjunctions?

Connectives join two separate ideas in two sentences or paragraphs. They usually come at the start of a sentence. and Conjunctions join two ideas in the same sentence.

Are conjunctions grammatically correct?

Coordinating conjunctions allow you to join words, phrases, and clauses of equal grammatical rank in a sentence. The most common coordinating conjunctions are for, and, nor, but, or, yet, and so; you can remember them by using the mnemonic device FANBOYS. I'd like pizza or a salad for lunch.