Its goal is to enable you to develop projects must faster than you could if you were writing code from scratch, by providing a rich set of libraries for commonly needed tasks, as well as a simple interface and logical structure to access these libraries.

Code Igniter lets the user creatively concentrate on the project by minimizing the amount of code needed for any given task or feature.

Code Igniter is right for:
A framework with a small footprint.
Not interested in large-scale, monolithic libraries, like PEAR.
Broad compatibility with standard hosting accounts that run a variety of PHP versions and configurations.
A framework that requires nearly zero configuration.
A framework that does not require you to use the command line.
Do not want to be forced to learn a templating language.
Exceptional performance.
To eschew complexity, favoring simple solutions.
Need clear, thorough documentation.