Continuous integration (CI) refers to the practice in which developers merge their produced code into the main branch as often as possible. The merged code should work without bugs and it should also provide value for the business. 

Using CI, we can automatically validate the committed code by running a set of automated tests. When we are using this practice, we are working on a CI codebase, avoiding the problems that arose in the past when scheduling a specific date and time to release a build.

With the CI approach, the most important goal is to automate the test to guarantee that the application is not broken any time the new commits are pushed into the main source code branch.