இந்த படத்தைப் பார்! – Look at this picture
இந்த படத்தைப் பாருங்கள்! – Please look at this picture
The main difference between the above two sentences is that the second sentence is more polite. The politeness is conveyed using the plural form of the verb, which is the imperative form of the verb plus the suffix -உங்கள்.
நீ . . . verb ‘do X’ [‘you’ singular]
(நீங்கள்) . . . verb -உங்கள் ‘please do X’ [‘you’ plural]