What really means "[homeassistant.loader] Loaded.."?

Configuration
1

Just for curiosity: looking in my log file when HA starts I find lines like these:

2019-03-30 08:48:04 INFO (MainThread) [homeassistant.loader] Loaded rainmachine from homeassistant.components.rainmachine
2019-03-30 08:48:04 INFO (MainThread) [homeassistant.loader] Loaded hangouts from homeassistant.components.hangouts
2019-03-30 08:48:04 INFO (MainThread) [homeassistant.loader] Loaded openuv from homeassistant.components.openuv
2019-03-30 08:48:04 INFO (MainThread) [homeassistant.loader] Loaded locative from homeassistant.components.locative
2019-03-30 08:48:04 INFO (MainThread) [homeassistant.loader] Loaded owntracks from homeassistant.components.owntracks
2019-03-30 08:48:04 INFO (MainThread) [homeassistant.loader] Loaded luftdaten from homeassistant.components.luftdaten

What really means?
Since, I don’t use any of these components I was wondering if this is overhead or not .