I can't see guide lines on selected paths anymore
When selecting a path or more paths with the Selection Tool or *Direct Selection Tool, I do not see the blue guide lines anymore. So I cannot know what is selected as well as how many anchor points are in a path. However when I put the mouse over a path, I can still see them.
How can I bring this blue lines (guide lines) back?
In addition to John's post, it could be...
View > Show Edges
And the short cut is Command/Ctrl + h
View > Smart Guides
And the short cut is Command/Ctrl + u