Windows Defender Protection History

Fads, styles, and fashions ebb and flow, come and go, in most fields.  And programming is no different.  There was a time when well programmed applications were considered "verbose" if they displayed on the screen every single line of code executed.  Antivirus software was usually very verbose as it scanned, listing the path of every file scanned.  Today's software trend is towards a more taciturn user interface.  Windows Defender is down right mute about its inner workings.  Unless you go look for what Windows has found and what it did about any such findings.  To do so, we must open Windows Security, which is available from the Notification Area where the clock is.

Next, Right click the Windows Security Icon.  Then Left Click View security dashboard.

Click Protection History.

The Protection History list will show what Windows Defender found in previous scans and what actions it took.  Items you might see listed:
PUPS (Potentially Unwanted Programs)  Usually adware but can be hostile

Trojan a type of Virus that allows other attackers into your computer*

Worm a type virus that self replicates*

Or might just say Virus.  * notes consider reformatting, at least.