Yes, they are.
For example double space, 1.5 spacing or any other you wish.
If you want to know how to double space or 1.5 space in MS Word, please see related link bellow.
Word 2007 - Line spacing
No
Answer by Semen: Yes, footnotes are single spaced by default regardless of the line spacing of the document text.
To change a document from single spacing to double spacing, go to the "Page Layout" or "Layout" tab in your word processing program, find the "Line Spacing" or "Paragraph" section, and select "2.0" or "Double" spacing. This will change the spacing throughout the entire document.
line spacing is used in a computer text document (such as Word). it is the space between each line of text examples: 1.5, double spaceing, single spacing.
Control 1 sets single line spacing. Control 5 sets 1.5 line spacing. Pressing Control 1.5 will set the document to single line spacing and then to 1.5 line spacing.
line spacing is used in a computer text document (such as Word). it is the space between each line of text examples: 1.5, double spaceing, single spacing.
Line spacing
paragraph
you highlight you document then you go to line spacing on the toolbar
Line spacing
Paragraph spacing refers to the vertical space between paragraphs in a document. To adjust paragraph line spacing in a word processing software like Microsoft Word, you can go to the "Home" tab, find the "Line and Paragraph Spacing" icon, and select the spacing option you prefer, such as single spacing, double spacing, or a custom spacing value. You can also adjust paragraph spacing by right-clicking on the paragraph, selecting "Paragraph", and then changing the line spacing in the dialog box that appears.