Define "picture" and "photograph".

[Eldrich]

the purpose of a picture is to capture the scene.
the purpose of a photograph is to capture the beauty of the scene.

 

[MikeBcos]

A picture is a visual representation of an object.

A photograph is a picture produced using a camera.

 

[bdavis]

the purpose of a picture is to capture the scene.
the purpose of a photograph is to capture the beauty of the scene.

I like that definition!

 

[Samanax]

I think more along the lines of "Snapshot" and "Photograph".

A "Snapshot" is a picture taken with no thought to composition, lighting, positive and negative space, no concern for the background, etc...you're just trying to capture a moment in time so you have something to remember it by. You basically just point and shoot.

A "Photograph" is more like a work of art where the photographer takes the time to think about everything that goes into making a good photograph...composition, lighting, positive and negative space, watching the background, etc... A photographer doesn't just point and shoot, he plans and thinks about the shot before he presses the shutter button.

 

[Slaphead]

You can paint, draw or sketch a picture, but you can only "take" a photograph.

 

[Breanna]

I'm purposfully not reading the other responses yet, as to not influence my own...

Picture: A snapshot, where the intention is to document. Visual information.
Photograph/photography: An image through an artist's eyes.

 

[Dagwood56]

Picture : A snapshot, a photo of a birthday party, or vacation etc.

Photograph : A carefully composed and exposed picture that tells a story - that "speaks" to someone visually.