Generally, IELTS Task 2 questions can be divided into 5 main types:

Sample Opinion Question

Space exploration is much too expensive and the money should be spent on more important things.

What is your opinion?

Sample Advantages & Disadvantages Question

Multinational companies are becoming increasingly common in developing countries.  

What are the advantages and disadvantages of this?

Sample Problem & Solution Question

Overpopulation of urban areas has led to numerous problems.

Identify one or two serious ones and suggest ways that governments and individuals can tackle these problems.

Sample Cause & Effect Question 

The percentage of overweight children in western society has increased by almost 20% in the last ten years.

Discuss the causes and effects of this disturbing trend.

Sample Discursive Question

Some people believe the aim of university education is to help graduates get better jobs. Others believe there are much wider benefits of university education for both individuals and society.

Discuss both views and give your opinion.

NB! However, it is always important to read the question carefully, as mixed types of essays are frequent. The candidate's task is to answer the question fully, so it is important to address all parts of the question equally.