All templates are stored in groups for your convenience. Usually, templates are arranged into groups in accordance with the context they are sensitive to.
Each group is represented by an xml file with the name <group>.xml; for example, css.xml. These files are stored in the config/templates directory that resides in the PyCharm's user settings directory.
PyCharm comes with a set of pre-defined groups of live templates. The user group, represented by user.xml file, is intended for storing custom live templates.
It is strongly recommended to avoid storing custom templates in the pre-defined PyCharm groups. For this purpose, use the user group, or a new group.