Compression and expansion of columns & rows

[Fahsid1230]

Hi Folks,
how can you make columns contract and extract using those special marker? I guess what I;m trying to ask you guys as how we incorporate the those dotted lines and little 1, 2 which makes the columns and rows for hide and unhide?
Any help will be appreciated.
Thx

 

[Makrini]

Highlight the rows you want

Go to menu - Data - Group and Outline - Group