Conjunctions

Conjunctions are words that connect words, phrases, or clauses. English language has three basic types of conjunctions: Coordinating Conjunctions, Correlating Conjunctions, or Subordination Conjunctions.

Coordination Conjunctions
This is the most common type of the conjunctions. The words that compound the coordination conjunctions are for, and, nor, but, or, yet, and so. These words are commonly used to join words, phrases, or clauses that are grammatically equal. A comma must be used before the coordination conjunction when it is used to connect two independent clauses.
A way to memorize these words is to use the acronym FANBOYS: 

For
And
Nor  
But  
Or   
Yet  
So  

Connecting words: Would you like water or juice?
Connecting phrases: In that bar there is no good nor good drinks.
Connection sentences: I’d like to stay, but I have to go. 

ATTENTION: Even though there are no grammatical rules forbidden starting the sentence with the coordination conjunction, it is not usual nor recommended.

Subordination Conjunctions
The subordination conjunctions are words that are used to link two clauses together, being a dependent and a independent clause.  A comma is used when the sentence is started with the dependent clause.
The most common subordination conjunctions are: while, as soon as, although, before, even if, because, no matter how, whether, wherever, when, until, after, as if, how, if, provided, in that, once, supposing, while, unless, in case, as far as, now that, as, so that, though, and since.

Starting with independent clause: I will stop watching TV because I have to study.
Starting with dependent clause: Because I have to study, I will stop watching TV.

Correlative Conjunctions
They are a peer of words that are used to join equal sentence element together.
The most common correlative conjunctions are: either… or, neither… nor, not only… but also, both… and, whether… or, and so… as

I love drinking chocolate either hot or cold.

ATTENTION: Besides the use of correlative conjunctions, don’t use more than one conjunction to connect words or phrases: Because I need to study, I will stop surfing on internet. NOT Because I need to study, so I will stop surfing on internet.

Conjunctive Adverbs
Conjunctive Adverbs are not conjunctions. However, these words are used to connect clauses too displaying sequence, contrast, cause and effect, among other relationships. 
The most common conjunctive adverbs are: accordingly, first, however, nonetheless, also, indeed, otherwise, besides, instead, similarly, still, likewise, consequently, conversely, meanwhile, subsequently, finally, moreover, then, therefore, furthermore, nevertheless, hence, next, thus.

First we arrived at that bar; then, we went to that night club.