Greenshot

Screen capturing

Capture full screen

Ctrl + Print Screen

All hotkeys for Greenshot

Screen capturing
Capture full screen

Ctrl + Print Screen

Screen capturing
Capture window

Alt + Print Screen

Screen capturing
Capture last region

↑   Shift + Print Screen

Screen capturing
Capture Internet Explorer

Ctrl + ↑   Shift + Print Screen

Drawing shapes
Rectangle

R

Drawing shapes
Ellipse

E

Drawing shapes
Line

L

Drawing shapes
Arrow

A

Drawing shapes
Freehand

F

Drawing shapes
You can hold this key to maintain existing object's aspect ratio while resizing

↑   Shift

Drawing shapes
Hold down to have the object anchored in it's geometrical middle

Ctrl

Exporting screenshot
Save image to a file

Ctrl + S

Exporting screenshot
Choose location and name to save the file

Ctrl + ↑   Shift + S

Exporting screenshot
Copy image to clipboard

Ctrl + ↑   Shift + C

Exporting screenshot
Send image to printer

Ctrl + P

Exporting screenshot
Open a new message in the default email client, add the image as an attachment

Ctrl + E

Other
Text tool

T

Other
Edit text

Mouse double click

Other
Finish editing

⤶ Enter

Other
Insert line break

↑   Shift + ⤶ Enter

Similar combinations for other applications

Linux Mint (Linux)
Copy a screenshot to the clipboard
Screenshots and Screen Recording

Ctrl + Print Screen

Screenshot taking
Copy screenshot of entire screen to clipboard
KDE / GNOME screenshot keys

Ctrl + Print Screen

Linux Mint
Take a screenshot and copy it to the clipboard
Frequently used shortcuts

Ctrl + Print Screen

ShareX
Capture area
General

Ctrl + Print Screen

IrfanView
Interactive screenshot tool
Tools and dialogs

Ctrl + Print Screen