Why does Mathematica import data with quotation?

Question

I am importing data from ParallelTable as dat file and then export it again for visualization. However, the exported data contains a quotation  " " and can not use ListPlot, here is an example
Y = ParallelTable[{x}, {x, -20, 20, 2}] // AbsoluteTiming;
Export["...\Hello3.dat", Y];
data = Import["...\Hello3.dat"];

the imported data has this form
{{0.0326645}, {"{-20}", "{-18}", "{-16}", "{-14}", "{-12}", "{-10}", 
  "{-8}", "{-6}", "{-4}", "{-2}", "{0}", "{2}", "{4}", "{6}", "{8}", 
  "{10}", "{12}", "{14}", "{16}", "{18}", "{20}"}}

If I use ListPlot[data[[2]]] it does not give output. So how can I avoid these quotations from the beginning with keeping AbsoluteTiming?

Αλέξανδρος Ζεγγ · Answer

Well, I have not dug very deep in this issue but just post my experience. And not about why but about how to get rid of the quotation marks.
When I deal with plaintext-wise data, I just use Put to store the data and later use Get to get it back in the same form as I Put it, without the requirement to set up other options. In your case, this should work:
Put[Y, "Hello3.dat"];
data = Get["Hello3.dat"]

No directory specified explicitly means that $UserDocumentsDirectory(at least in Win 10) is used. You can specify other directory if you prefer.

Why does Mathematica import data with quotation?

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