Hi Shivani,
Adding to Scott comments--
what is eclipse?
Eclipse: It is basically a Java IDE tool to build the Java/J2EE projects, we can create AEM projects in eclipse and build the same.
how to integrate eclipse to aem?
There is an AEM Eclipse plugin to integrate AEM with eclipse. With this you can create the AEM project using the plugin and also you can import/export from servers. See below link for your reference.
http://www.aemcq5tutorials.com/tutorials/configure-aem-plugin-for-eclipse/
Also there is Brackets tool to integrate AEM with brackets, you can modify your HTL aka sightly directly.
Alternatives of eclipse?
You can use IntelliJ as an alternative to eclipse.
how to install maven?
You can install maven by looking to this article: Creating Adobe Experience Manager 6.4 Sling Servlets that invoke MBean operations
Also, I perfer version of maven is 3.5.x. AEM works very well with this version.
which maven version is preferred with aem? what is the issue with smaller version of maven in aem?
Smaller version of Maven won't support some dependencies/plugins that comes with AEM higher version. So prefer maven higher version i.e., 3.5.x.
why we need maven in aem?
Maven is basically a build tool and it is recommended to build the AEM projects. Below is the HELPX article shows how you build AEM project using Maven archetype 13
Creating an Adobe Experience Manager 6.4 Project using Adobe Maven Archetype 13
Alternatives of maven?
You can also using Gradle tool to build AEM projects as an alternative to Maven.
what is logging and brief discription about logging in aem?
Logging is basically used to see the Error messages, info messages etc. It helps you to debug the error in AEM. Check here for more information,
AEM Developer Learning : AEM Logs in detail - Part 1
how to use logging in aem and which tool we are using for logging?
See here for how to use Logging in AEM and there is no tool for logging: Creating a custom log file for an Adobe Experience Manager project
Hope this helps!!!
Thanks,
Ratna Kumar.