What difference between std.typecons.Tuple and std.meta.AliasSeq

[Suliman via Digitalmars-d-learn]

Sometimes it's hard to understand the D philosophy, for example 
now I can't understand diffrence between std.typecons.Tuple and 
std.meta.AliasSeq. I know that in language like Python there is 
spatial data type named tuple like:
tup1 = ('physics', 'chemistry', 1997, 2000);

But what in D? That was Tuples module, but it's look like it was 
renamed to 
http://forum.dlang.org/thread/mnhfhs$2b9o$1@digitalmars.com

But look like std.typecons.Tuple and std.meta.AliasSeq are 
exists. So I really can't understand what and how I should to use 
that's all.