What is the difference between set complete+=t and set complete+=k in vim?

Question

In this wikia tip I found set complete+=k and set complete+=t. I applied both but only the first one worked.

My question is what is the difference between these?

Answer 1

From :h 'complete':

k   scan the files given with the 'dictionary' option
]   tag completion
t   same as "]"

The tag k allows you to specify a file containing some words you want to use for completion. The tag t is used to complete tags generated by a program like exuberant Ctags or cscope. For more details about tags see :h tag.

When you used set complete+=t it's not that it didn't work it is that you probably didn't generate a tag file.