Why does a zigzag line appear under text?

[Karl]

A sort of zig zag line sometimes appear under text typed. Why is that and
how can I get rid of it?

 

[Barbara]

A red zigzag means Word thinks there is a spelling error. A green zigzag
means Word thinks there is a grammatical error. In either case, right-click
on the word and select an option from the pop-up.

 

[grammatim]

In order to never see the red and green squiggles, go to the controls
for Spell Check (wherever they are in your version) and uncheck the
"check spelling" and "check grammar" boxes.

Also you might see very faint dotted lines under familiar names. To
get rid of those (utterly useless) dotted lines, uncheck the
"SmartLinks" option that might be under Options View or Options
General.

 

[Suzanne S. Barnhill]

For an explanation of all these lines (Word calls them "wavy" lines), see
the Help topic "What do the underlines in my document mean?" For even more
information (on underlines and other marks), see "I see something unusual in
my document."

 

[Henk57]

A sort of zig zag line sometimes appear under text typed. Why is tha
and
how can I get rid of it?

It looks like it's a spelling or grammar checker indication. If so, g
to Tools/Options/Spelling & Grammar. Clear "Check spelling as you type
to get rid of them