# Mathematica ExtraPackage

Where can I install the Wolfram ExtraPackages? Especially the "Notation" package? I do not seem to have it by default (In the Utilities, I have only two documents, called CleanSlate.m and URLTools.m) and I cannot find any information on that.

You can easily get the path to any installed package file using FindFile, for example:

FindFile["Notation"]

"C:\\Program Files\\Wolfram Research\\Mathematica\\11.3\\AddOns\\Packages\\Notation\\Kernel\\init.m"


If the package isn't installed, you could search it in several places on the Internet. Don't forget about this site, old Wolfram Library Archive and also brand-new Wolfram Function Repository.

Oh ok, so after some further reading, it seems that doing:

<< Notation


does the trick. I was trying to do something like

Needs[UtilitiesNotation]


but with no success. I am not very sure where Wolfram takes the package from though?

• I believe the Notation package can be found by calling SystemOpen[$InstallationDirectory] and then navigating to the folder AddOns > Packages. These are all preinstalled packages, they just aren't loaded into system memory when Mathematica is opened (presumably to reduce load times and memory usage for typically non-critical packages). – MassDefect Jan 7 '19 at 19:19 • It is exactly as MassDefect said. You can open the folder directly with SystemOpen@ FileNameJoin[{$InstallationDirectory, "AddOns", "Packages", "Notation"}]. – Henrik Schumacher Jan 7 '19 at 19:33
• and you could have used Needs["Notation"] or Get["Notation"] just as well. << is just a shortcut for Get and will automatically convert its argument into a string. Both Get and Needs should work and usually Needs` is the better choice. – Albert Retey Feb 14 '19 at 14:08