Update:
As of Jan 2022, I do see updates and fixes being released for Shutter so the below update I do not think is still apt. For e.g. they just pushed a release 0.99.2 on Oct 24, 2021.

Update:
As of Aug 2018, Shutter project hasn't had a release or security fix since 2014. Many key libraries are depreciated, it may not exist beyond Ubuntu 18.04. Consider a newer maintained alternative, such as one of the projects listed below. Know of something new and missing? Add it!

I am using Shutter .

If you don't find it, you can check the detailed installation instructions which will give you a PPA for it.

It's a really handy screen capture application with easy to use plug-ins to give a nice touch to your screenshot and as many other to easily share the files.

It offers in-house image editing and special effects (via plug-ins) to enhance the quality of your screenshot. You can access this options via the menu (1), or the toolbar (2).

The effects here are all done with Shutter (Plug-in Reflexion and Edit auto-increment shape).

And then to publish them, I just right click in Shutter and choose Export (3). Then I publish it via Ubuntu One. I go to the directory where I published the file, right click on it and select Copy Ubuntu One public URL.

Finally here when I comment, I click on img in the small tool bar and select From the web and paste the link that was copied in the previous step.

It's easy and fully integrated.

For those on 10.04, check that you have all shutter dependencies. As you might miss some of the plug-ins. For user on Ubuntu 10.10, this should be fixed.

GNOME Screenshot

I find the GNOME screenshot tool to be the most effective of all. And it is installed by default!

My favorite is the use of shortcuts to quickly generate images. For example - Print Screen which takes the entire desktop and Alt+Print Screen for the current focused window.

Furthermore the interface is extremely simple and powerful for such a small tool.

It provides nearly the same functionality as the Snipping Tool in Windows via the Select area to grab option, but you can also make a screenshot of a window without the window frame and shadow.

Since Ubuntu 14.04, including 16.04, and 18.04, simply press

• Prt Scrn to take a screenshot of the desktop,
• Alt+Prt Scrn to take a screenshot of a window,
• Shift+Prt Scrn to take a screenshot of an area you select.

The screenshots will be saved to ~/Pictures.

It is included in Official Documentation online help, Ubuntu Stable: Tips & Tricks: [Screenshots and Screencasts] 4.

Flameshot

A powerful open source screenshot and annotation tool for Linux, Flameshot has a varied set of editing tools available, including:

• Freehand drawing
• Lines
• Arrows
• Boxes
• Circles
• Highlighting
• Blur
• Save image, or upload to Cloud (Imgur), or copy to clipboard
• Add Text (Available in version 0.6 )

You can customize the color, size and/or thickness of many of these image annotation tools.

Install

Flameshot is directly available in 18.04 from the universe/graphics repository. Usage info in man page.

Additional installation options, such as how to compile with latest features or installation on older/other distros, are available on project page. Note: Latest version installed from source has cool features (not yet released); but will be included in version 0.6.

I recommend using the command line tool scrot as it is easy to use and, unlike import, it supports transparency.

To install:

sudo apt-get install scrot

To capture a screen area:

scrot -s /tmp/foo.png

Screencloud

There is a new kid on the block of screenshot utilities: screencloud

It's a pretty cool tool, available in the Ubuntu Software Center (at least on Ubuntu 12.04).

It has many nice features to easily share the screenshots via the Internet, hence its name.

• Upload the screenshot to screencloud. The link is automatically pasted to your clipboard;
• You can use an FTP or SFTP own server for this kind of sharing
• It's multi-platform.

I use GNOME Screenshot, but for the sake of the reference and for all the old timers you can use xwd from the command line:

For a screenshot of your entire screen:

xwd -root | convert xwd:- out.png

I use GIMP. It has a nice tool which allows you to pause (to move it out of the way) and to select just a portion of the window. Usually I crop or edit a screenshot after taking it, so I want to be in GIMP anyway.

GNOME Screenshot does the job fine for me, but there is also ImageMagick for CLI-oriented folks:

import screenshot.png
import -window root screenshot.jpg

But, same as xwd, it will not work well with Compiz.

There is also Nanoshot - more simple than Shutter.

sudo add-apt-repository ppa:nanoshot/ppa
sudo apt-get update
sudo apt-get install nanoshot