Subject: How do the various types of pipette differ from each other in purpose?

I understand that Pasteur pipettes are made of plastic but am unsure whether or
not they can be used for measuring substances. Is their purpose only to
transport substances, not measure them?
Also, is a Pasteur pipette the same as a dropper pipette? How does a Pasteur
pipette differ from other types of pipettes found in a chemistry lab?

Is it only the glass pipettes and the other type of pipette that look like this:

http://www.bing.com/images/search?q=pipette&view=detail&id=D32FDB5919AE17F3879BAFC3EC664898CFC2FC07&first=1&FORM=IDFRIR
that are used to measure volumes of substances?

Thank you

Re: How do the various types of pipette differ from each other in purpose?