The Reflexive Pronouns versus personal pronouns

Question

What is the difference between reflexive pronouns and personal pronouns.

I am making a chart with all cases in different situations - as this is where I am in my learning.

I am confused when to use what, and what the difference is between certain variations in the two. See the below charts:

(Nevermind ihr being circled)

So I have a few questions that would clear some stuff up:

(1) When would I use ihm instead of sich and so on? Basically what I am asking is, why are some reflexive pronouns in the accusative and dative cases, such as mich, mir, the same as the personal pronoun accusative and dative cases? While some, like the case for er (ihn, ihm, sich), do not.

(2) I noticed that Wikipedia has unser and euer for the personal pronoun genitive case. This other chart which is from http://www.german-exercises.de/ has unserer and euerer. Which is correct? Why the discrepancy?

(3) Also is there a Ref-Genitive case?

Answer 1

If disappointing, but they are the same because they are the same. There's no appropriate explanation other than that. I highly doubt that it's helpful to try to understand the historical reasons here.

Sich is reflexive. You use sich when you refer back to the subject. Ihm is used if the object is a different person (or thing).

Er hat sich ein Buch gekauft. (He bought a book for himself.)
Ich habe ihm ein Buch gekauft. (I bought a book for him.)

Unser and unserer are both correct. Take a look at the complete table for unser. As you see it depends on whether you use it as an attribute (preceding a noun) or as a pronoun (instead of the noun). And it also matters whether you apply the article or not. To understand this further, you should look up the terms weak, mixed and strong inflection. There are also many questions on this site.

Unser Baum ist groß.
Unserer ist größer.
Der unsere ist am größten.

And no, there's no reflexive form for genitive. It doesn't make any sense after all.
As Emanuel correctly says, there is a reflexive form in the genitive case. This, however, is used very rarely.

Answer 2

The apparently contradiction really isn't one because the tables are going in different orders.

For example, the first table goes "mir, dir, ihm, ihr, ihm" for "ich, du, er, sie, es".

In contrast, the second table goes "mir, dir, ihm, ihm, ihr" for "ich, du, er, es, sie".

The only difference is that the second table, for no apparent reason, chose to write "er, es, sie" instead of the typical order of "er, sie, es." That's all.