Your question is really beyond the scope of APUG. You need to get a book like L F A Mason, Photographic Processing Chemistry or Pierre Glafkides, Photographic Chemistry. All your questions will be answered there. As a start here is a partial list.
Classes of Developers
Film developers may be divided in classes according to their action upon the
emulsion and their mode of use.
Fine-Grain Compensating Developers
Fine-grain compensating developers achieve their extremely fine grain due to their
low alkalinity and relatively slow development rate. While these developers
produce normal gradations it is at the expense of film speed. Exposure must
be carefully controlled since other than optimal exposure will result in an
increase in graininess.
Examples of fine-grain compensating developers are Agfa Refinal, Kodak
D-23 and Ilford Perceptol.
Fine-Grain Developers
Fine-grain developers contain one or more substances which dissolve some <BR>
of the silver halide and encourage physical development. This results in <BR>
extremely fine grain. The characterisic curve produced has a long straight <BR>
line portion with very little sag.
Examples of fine-grain developers are Kodak D-25 and Harvey's Panthermic <BR>
777.
Emulsion Surface Developers
Emulsion surface developers, due to their extreme dilution, work only near
the surface of the emulsion. This enhances definition and greatly lessens
halation and scattering even for long exposures. Because of the nature of
their action, this class of developers is not well suited for drum development.
Examples of emulsion surface developers are Rodinal, FX-1 and the Beutler
formula.
Universal Developers
Universal developers are suitable for all film emulsions. Negative contrast,
acutance, and compensation may be controlled by varying the dilution.
Examples of universal developers are Rodinal and the D-72.
Multivalent Character Developers
Multivalent character developers are designed for modern emulsions and in
particular tabular grain films. These formulas produce a good balance of
grain, sharpness, resolution and tonal rendering. While designed principally
for tabular grain films other films can also be processed with good results.
Examples of multivalent character developers are Kodak TMAX developer
and the FX-37 formula.
General Purpose Developers
Kodak D-76, Ilford ID-11
Staining developers
Kodak D-1
Special Purpose developers
POTA, Delagi, Perfection XR-1