‘All rights reserved’ means that you have to ask permission from the creator (or his assigns, such as inheritors or publisher) before you can use the work.
Sometimes there are exceptions to this main rule, for example the Easy Access Agreement or the right to quote, so that you do not have to ask permission from the creator. Make sure you always carefully refer to the source.
‘Some rights reserved’ means that a work may only be used under certain conditions. See also the Creative Commons website for an explanation of the different types of licences used for this purpose.