Simply speaking, computational chemistryis a branch of chemistry that uses the concepts of theoretical chemistry and takes the assistance of computers and solves problems related to chemistry. A detailed lecture series including theory of ab initio, DFT, semi emperical and Molecular Mechanics alongwith a brief guide on how to use Gaussian Softwarethrough GaussViewcan be found at the Nick Mosey's webpage. GaussView is the software used to build/view molecules whereas the actual calculations are run in Gaussian suite of programms.

There are a variety of softwares available for computational chemist. Some softwares can perform a variety of calculations where as others are specific for a particular type of Calculation. A brief list of different types of calculations softwares are:

1. BiomolecularModelling (Docking) for Proteins and Enzymes
2. Molecular Mechanics
3. Quantum Mechanics
4. Semi Emperical
5. Valence Bond
6. Molecular Desing Software

A complete listof computational softwares can be found here. Most commonly used softwares are:

1. Docking/Biomolecular

a. AutoDock

b. Gold

c. AutoDockVina

d. Flexx

2. Quantum Machenical

a. Gaussian

b. Gamess (US)&Gamess (UK)

c. Spartan

d. FireFly

e. Jaguar

f. Polyrate

g. MolPro

Gaussian Help Sources

1. Gaussian keywords
2. CCL discussion forum for computational help
3. Gaussian examples page
4. Dr. Joaquin Barroso's Blog

Focus Areas

1. Mechanistic understanding of chemical transformations, particularly focused on catalysis
2. Photoswitches
3. Conducting polymers
4. Frustrated lewis pairs
5. Aromaticity
6. Theoretical estimations of non-covalent interactions biologically important complexes. 
7. Dyotropic rearrangement
8. Bechmark study
9. Non-linear optical studies