There are two IELTS modules. One decides which one to take based on his needs.
The Academic Training
This module is taken by those who want to study in a university or in any higher education institution in an English Speaking country or for registration in a professional body.
The General Training
This is for those who want to study secondary education or high school or for immigration purposes.
Comparison
In both modules, Listening and Speaking are the same but they vary in Reading and Writing.
In writing Task 1, it's describing a graph, chart, table or diagram in academic, while in general it is letter writing.
In reading, they are almost the same except the source of the texts.
The
Listening module
has 40 questions to be answered in 30 minutes.
The
Speaking module
is about 11-14 minutes consisting of 3 parts.
The
Reading module
has 3 passages, 40 questions to be answered in 60 minutes.
The
Writing Module
has 2 tasks. Task 1 and 2 must have no less than 150 and 250 words respectively.