Append Columns to a Table?

Questions
1

I imported a csv file into Mathematica and I want to append columns to it:

Append[Data[[i]], Cycle[i][[15, j]]], {i, 1, Length[CycleStartTime]}];

This allows me to append one column, what if I want to append more columns?

2

You may use Join:

In[1]:= Join[{{a, b}, {c, d}}, {{1, 2}, {3, 4}}, 2]

Out[1]= {{a, b, 1, 2}, {c, d, 3, 4}}