Below files are necessary files to build a component in Joomla :
On admin side :
* component_name.xml
* install.component_name.php
* uninstall.component_name.php
* toolbar.component_name.php
* uninstall.component_name.html.php
* admin.component_name.php
* admin.component_name.html.php
* component_name.class.php
On front side :
* component_name.php
* component_name.html.php
