A little convenience feature that could be suitable to mention in this context
is the -G or --get option, which takes all data you have specified with
the different -d variants and appends that data to the inputted URL
e.g. http://example.com separated with a '?' and then makes curl send a
GET instead.
This option makes it easy to switch between POSTing and GETing a form, for example.
An example that adds an encoded piece of data as a query in the URL:
curl -G --data-urlencode "name=daniel stenberg" https://example.com/