Create Mywork_ImageSlider.xml file

Firstly create the Mywork_ImageSlider.xml file in app/etc/modules/

<?xml version="1.0"?>

Note:- 1) If you want to active the extensions then use true otherwise false.
2) there is three code pool (a) local (b) core (c) community
when we create the own extension then we use local code pool.
3) When this extension call then firstly call this file, if active true then run otherwise not run.