What is T in Convariance Matrix?

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Wikipedia-style definition page for the covariance matrix: column vector X of random variables, entries of the covariance matrix defined as cov(Xi, Xj), the n by n matrix of expectations, and the matrix form E[(X - E[X])(X - E[X])^T].


My question is what is the the meaning of the T(as a power) in the following line?

Covariance matrix formula: Sigma = E[(X - E[X])(X - E[X])^T], where the superscript T denotes transpose.
https://www.physicsforums.com/showthread.php?p=4463256#post4463256
 
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That just means the transpose. That line is a concise way of generating the matrix you see above it. Each cell is ##E[(X_i - μ_i)(X_j - μ_j)]## where i,j are the row,column indices of each matrix cell. The multiplication with the transpose matches i and j in just the right way.