Default Web Server on Mac

The web server can be started on my in any directory through the following command:

# python -m SimpleHTTPServer 8000

(port number can be changed) 

or the default apache server can also be started through: 

# sudo apachectl start

The default localhost folder located here: /Library/WebServer/Documents or as per
configuration in apache2 config files.

Default apache is installed in /etc/apache2/ with all
its configuration files (httpd.conf).

Multiple eclipse instances on Mac

OSX Eclipse Launcher utility plugin

Follow these simple instructions

1. Go to help --> Eclipse Marketplace...
2. Search for "OS X Eclipse laucher utility"
3. Cick Install, Next, Finish and restart your eclipse.

Once the plugin is installed, click on File --> Open Workspace.  Here you go, a new instance of eclipse is opened with a new workspace.