All the files are located under this directory by default:
Windows Vista, 7, 8, 10:
<SYSTEM DRIVE>\Users\<USER ACCOUNT NAME>\.<PRODUCT><VERSION>
<SYSTEM DRIVE>\Documents and Settings\<USER ACCOUNT NAME>\.<PRODUCT><VERSION>
Sample paths for different products
Under this directory you'll find the following sub-directories
config: configuration (idea.config.path)
configplugins: plugins (idea.plugins.path)
system: caches, local history, etc (idea.system.path)
systemlog: logs and thread dumps (idea.log.path)
You can find more details about what is stored in each folder in the Project and IDE Settings documentation section.
Linux and other Unix systems
Product directory starting with dot can be found in your user home directory, the pattern is:
~ is an alias for the home directory, for example /home/john.
Mac OS X