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What is meant by the word standard in "Euclidean space is special in having a standard set of global coordinates."? Then "A manifold in general does not have standard coordinates" This makes me think standard means something else then 'most common used'. Is R^n special in any sense, as a manifold?

This is from Loring W. Tu - Introduction to manifolds

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    As an aside, this "special" circumstance occurs for the $n$-fold cartesian product $R^n$ for any ring $R$ with unity. For, if $1$ denotes the multiplicative unit in $R$ then any element $r \in R^n$ where $r = (r_1, \dots, r_n)$ can be expressed as $r = r_1(1, 0, \dots, 0) + \dots + r_n(0, \dots, 1)$2012-04-04

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Usually when we write "$\mathbb{R}^n$" we are thinking of an explicit description of it as $n$-tuples of real numbers. This description "is" the standard set of global coordinates, namely the coordinate functions $x_i$. But this description isn't part of $\mathbb{R}^n$ "as a manifold", in that it contains more information than just the diffeomorphism type of this manifold. What I mean by this is that if I give you an abstract manifold which is diffeomorphic to $\mathbb{R}^n$ -- but I don't tell you an explicit diffeomorphism -- then there isn't a "standard" set of coordinates for it. And if you have a manifold which isn't diffeomorphic to any $\mathbb{R}^n$, then there is no set of global coordinates for it (otherwise you could use those coordinates to produce a diffeomorphism to $\mathbb{R}^n$).