Ask Ubuntu is a question and answer site for Ubuntu users and developers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I have come across several installation instructions that include the command deb. But it appears that this command is not available on my installation.

Where can I get this command? Is there a work-around?

share|improve this question
Please accept an answer to questions where you have a good answer, to show that you like an answer and it helped you the most. You can do so with the checkmark to the left. – hexafraction Dec 26 '12 at 23:20
I'm embarassed that I didn't realize the instructions I was reading weren't showing me something to type at the command line, it was showing me a line to put in a file. I'm glad you asked this question! – Tyler Collier Oct 13 '13 at 5:40

'deb' is not a command. It is used in sources.list file to indicate a Debian software repository.

From Ubuntu Manpage - sources.list:

The source list is designed to support any number of active sources and a variety of source media. The file lists one source per line, with the most preferred source listed first. The format of each line is: type uri args. The first item, type determines the format for args. uri is a Universal Resource Identifier (URI), which is a superset of the more specific and well-known Universal Resource Locator, or URL.

The deb type describes a typical two-level Debian archive, distribution/component. The format for a sources.list entry using the deb and deb-src types is:

deb [ options ] uri distribution [component1] [component2] [...]

The URI for the deb type must specify the base of the Debian distribution, from which APT will find the information it needs. distribution can specify an exact path, in which case the components must be omitted and distribution must end with a slash (/). This is useful for when the case only a particular sub-section of the archive denoted by the URI is of interest. If distribution does not specify an exact path, at least one component must be present.

So, if I have deb quantal main restricted in sources.list it says I have a Debian archive which is based on "", the distribution is "quantal" and the components are "main" and "restricted".

share|improve this answer
And sources.list is in /etc/apt/ on 12.04. – Ahmed Fasih Dec 4 '13 at 15:36
Can be useful if you say that "deb" lines are instructions added to Aptitude source lists. That would eliminate the amount of confusion this whole issue creates. – Shehi Jan 27 '14 at 10:08

like answer by @Eric Carvalho deb is not command line If you have deb then url like this:

deb trusty contrib 


like commit of @muru, you need to create new file with extension .list into /etc/apt/source.list.d/ folder:

Example: I want to download Oracle virtualbox, create new file :

sudo gedit /etc/apt/sources.list.d/oracle-virtualbox-trusty.list 

Then copy and past the line of deb into this file

share|improve this answer
1. It's apt, not opt (though there is an opt) and 2. Never edit /etc/apt/sources.list to add a line unless it is an Ubuntu mirror/official repository. Create a new file in /etc/apt/sources.list.d with the extension .list with that line. – muru Sep 11 '14 at 16:02
@muru "Never edit /etc/apt/sources.list to add a line unless it is an Ubuntu mirror/official repository." Why? Sure, making .list files in /etc/apt/sources.list.d is what I do under these circumstances and is what I usually recommend. But I see no reason to insist manually added 3rd party software sources go in /etc/apt/sources.list.d. Some conffiles are when possible best not edited by the user (e.g., use /etc/profile.d over /etc/profile, arguably use /etc/sudoers.d over /etc/sudoers), but sources.list is often changed. (Even customized by Ubiquity to a regional mirror.) – Eliah Kagan Sep 12 '14 at 6:06
@EliahKagan when have you ever seen Ubiquity add a third-party repository (not mirror) to sources.list? Or for that matter, any official tool? sources.list.d is present for a reason. I will continue to insist that it be used for third-party repositories. – muru Sep 12 '14 at 7:41
@muru Sorry, I wasn't clear. I mentioned Ubiquity's behavior to point out /etc/apt/sources.list isn't one of the conffiles that one can leave alone so as to facilitate smoother upgrading--as that is often (perhaps usually) the motivation behind strong suggestions to prefer making files in X.d to editing X. I am not suggesting Ubiquity enables third-party repos in any way. You haven't explained what's special about such repos, though, so as to make it actually wrong (i.e., "Never edit...") to put them in sources.list. – Eliah Kagan Sep 12 '14 at 7:49
@EliahKagan There's nothing "actually wrong" in doing so, if that's your problem with the statement. "Never [do X]" doesn't always mean that doing X is wrong, it can and does mean that doing X is bad practice ("Never use GOTO."). Happy, now? Repeat: I will continue to insist that sources.list.d be used for third party repositories and sources.list only for mirrors and official repos, unless you can give me a clear, sound, reason as to why it is a good idea not to do so. – muru Sep 12 '14 at 8:05

Deb isn't actually a command (I thought so too, at first) -- Assuming you are trying to download/install a deb, do this (for example):


then dpkg -i whatever.deb

then run the commands:

sudo apt-get update
share|improve this answer
This is not relevant at all. – Pilot6 Jul 16 at 16:17
100% relevant, and better than the best answer above. He's obviously trying to download/install a .deb – Dylan Hunt Jul 17 at 17:33

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.