diff --git a/collector/system.go b/collector/system.go
index 83ae9e1c..051da15b 100644
--- a/collector/system.go
+++ b/collector/system.go
@@ -30,37 +30,37 @@ func NewSystemCollector() (Collector, error) {
 	return &SystemCollector{
 		ContextSwitchesTotal: prometheus.NewDesc(
 			prometheus.BuildFQName(Namespace, subsystem, "context_switches_total"),
-			"PerfOS_System.ContextSwitchesPersec",
+			"Total number of context switches (WMI source: PerfOS_System.ContextSwitchesPersec)",
 			nil,
 			nil,
 		),
 		ExceptionDispatchesTotal: prometheus.NewDesc(
 			prometheus.BuildFQName(Namespace, subsystem, "exception_dispatches_total"),
-			"PerfOS_System.ExceptionDispatchesPersec",
+			"Total number of exceptions dispatched (WMI source: PerfOS_System.ExceptionDispatchesPersec)",
 			nil,
 			nil,
 		),
 		ProcessorQueueLength: prometheus.NewDesc(
 			prometheus.BuildFQName(Namespace, subsystem, "processor_queue_length"),
-			"PerfOS_System.ProcessorQueueLength",
+			"Length of processor queue (WMI source: PerfOS_System.ProcessorQueueLength)",
 			nil,
 			nil,
 		),
 		SystemCallsTotal: prometheus.NewDesc(
 			prometheus.BuildFQName(Namespace, subsystem, "system_calls_total"),
-			"PerfOS_System.SystemCallsPersec",
+			"Total number of system calls (WMI source: PerfOS_System.SystemCallsPersec)",
 			nil,
 			nil,
 		),
 		SystemUpTime: prometheus.NewDesc(
 			prometheus.BuildFQName(Namespace, subsystem, "system_up_time"),
-			"SystemUpTime/Frequency_Object",
+			"System boot time (WMI source: PerfOS_System.SystemUpTime)",
 			nil,
 			nil,
 		),
 		Threads: prometheus.NewDesc(
 			prometheus.BuildFQName(Namespace, subsystem, "threads"),
-			"PerfOS_System.Threads",
+			"Current number of threads (WMI source: PerfOS_System.Threads)",
 			nil,
 			nil,
 		),
@@ -96,12 +96,12 @@ func (c *SystemCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc
 
 	ch <- prometheus.MustNewConstMetric(
 		c.ContextSwitchesTotal,
-		prometheus.GaugeValue,
+		prometheus.CounterValue,
 		float64(dst[0].ContextSwitchesPersec),
 	)
 	ch <- prometheus.MustNewConstMetric(
 		c.ExceptionDispatchesTotal,
-		prometheus.GaugeValue,
+		prometheus.CounterValue,
 		float64(dst[0].ExceptionDispatchesPersec),
 	)
 	ch <- prometheus.MustNewConstMetric(
@@ -111,7 +111,7 @@ func (c *SystemCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc
 	)
 	ch <- prometheus.MustNewConstMetric(
 		c.SystemCallsTotal,
-		prometheus.GaugeValue,
+		prometheus.CounterValue,
 		float64(dst[0].SystemCallsPersec),
 	)
 	ch <- prometheus.MustNewConstMetric(