How do I insert a piece of code in Mathematica?

In Fortran, I can use include "file" to insert a piece of code. Is there a similar method in Mathematica?

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Have a look at the docs on packages. –  b.gatessucks Dec 27 '12 at 13:45
@b.gatessucks I think that should be an answer... –  acl Dec 27 '12 at 14:43
@acl Can't do it right now, please do go ahead. –  b.gatessucks Dec 27 '12 at 17:12

Put your external code snippet into a file toInclude.m, for example with the content

Plot[Sin[x],{x,0,Pi}]


Now in the "parent" notebook (assuming it's in the same directory as the code snippet), execute the command

Import["toInclude.m"]


or

<< "toInclude.m"


and you're done. Here are the references for << (Get) and Import.

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