Each column is a tiddler, rows are fields

code: <<ColumnTable '[tag[Column Data]]'>>

	Column Data Thing	Column Data Thing 1	Column Data Thing 2
fifth	–	–	bar
first	2	eddie	eddie
fourth	ed	–	foo
second	5	joe	joe
third	5	something	bob
type	text/vnd.tiddlywiki	text/vnd.tiddlywiki	text/vnd.tiddlywiki

Each row is a tiddler, columns are fields

code: <<RowTable '[tag[Column Data]]'>>

Title	fifth	first	fourth	second	third	type
Column Data Thing	–	2	ed	5	5	text/vnd.tiddlywiki
Column Data Thing 1	–	eddie	–	joe	something	text/vnd.tiddlywiki
Column Data Thing 2	bar	eddie	foo	joe	bob	text/vnd.tiddlywiki

Or list both columns and rows

When you do this the difference between ColumnTable and RowTable is if column headers are tiddlers with the rows stored in the fields of the tiddlers or if the row headers are tiddlers with the columns stored in fields. This is important because field names have more restrictions that tiddler titles.

code: <<ColumnTable '[tag[Column Data]]' 'first second fifth'>>

	Column Data Thing	Column Data Thing 1	Column Data Thing 2
first	2	eddie	eddie
second	5	joe	joe
fifth	–	–	bar

code: <<RowTable '[tag[Column Data]]' 'third second fifth'>>

Title	third	second	fifth
Column Data Thing	5	5	–
Column Data Thing 1	something	joe	–
Column Data Thing 2	bob	joe	bar

Note that for both of them the rows and columns don't have to be existing fields or tiddlers, you can create a table that doesn't use existing tiddlers and when you edit the values for each cell the tiddler is created.

code: <<ColumnTable """[[This Tiddler]][[Does not Exist]]""" "[[these_ones]][[must_be]][[valid]][[field_names]]">>

	Does not Exist	This Tiddler
these_ones	–	–
must_be	–	–
valid	–	–
field_names	–	–