What's the difference between 拍照 (pāizhào) and 照相 (zhàoxiàng) which both mean "to take a photo"? These two words seem very similar:


拍照 (pāizhào) = "to take a picture" (dict.cn） or "take a photograph (pt took) (pp taken)" (Collins)
照相 (zhàoxiàng) = "take a photograph" (dict.cn） or "take a picture (pt took) (pp taken)" (Collins)


Question: What's the difference between 拍照 and 照相?

Jukuu.com gives many example sentences for 拍照; here's some simple ones:


  你不要动, 我给你拍照 (Nǐ bùyào dòng, wǒ gěi nǐ pāizhào)
  爸爸为她拍照 (Bàba wèi tā pāizhào)
  禁止拍照 (Jìnzhǐ pāizhào)
  你喜欢拍照什么? (Nǐ xǐhuān pāizhào shénme?)


Judging from Baidu results, in the first two cases above, we can replace 拍照 with 照相, but not in the second two cases.  So there seems to be some difference.
The two terms have the same meaning of "take photograph" in modern Chinese, they just describe the same action differently.


'照' in '照相' refers to 'reflect with mirror' and 相 is short for 相片 (portrait/ photograph). Taking photograph with early cameras required the subject to stand still for few minutes, facing the lens like facing a mirror; even with modern cameras, the subject still need to stand still in front of the camera lens to have his or her picture taken.
'拍' in '拍照' refers to the 'clicking' sound of the camera. and '照' is short for '照片' (photograph). when you push the camera button, the shutter would open and shut and make a 'clicking' sound. 


(it might also refers to the loud flashing sound the early camera flashlight made)

照相 probably was coined before 拍照. In early days of cameras, the only way to take a photograph of yourself is  go to 照相館-- We never heard of '拍照館' And taking picture of a person or a family was the sole function of 照相館. 

Also, we have 禁止拍照 signs but not 禁止照相 signs. 禁止拍照 mainly targeted handheld cameras. With handheld cameras, we can take picture other than people, therefore, 拍照 can mean taking picture of people, scenery or object; While 照相 mainly means taking portrait of people.