Learn English – When to use “nowhere” and when “not anywhere”

Breaking this down:

• and/or is as official as English gets in the sense that you can use it in extremely formal contexts. There is typically a better way to say whatever is being said but it does convey a specific meaning.

• You should use and/or when both options are applicable in its place. "I would like cake and/or pie" means "I would like one or both of the following: cake; pie."

• The main reason for using and/or is to remove the ambiguity of whether and means "only both" and whether or means "only one." And/or explicitly means "it could be one of these or both of these."

• The confusion is drastically exacerbated by mathematicians, logicians and/or computer scientists who are very familiar with the differences between the logical operators AND, OR, and XOR. Namely, or in English can be either OR or XOR; and/or can only mean OR. As you may have noticed, all of the terms look similar which leads to the confusion in parsing sentences like your title.

EDIT: To strictly answer the question, you should use A and B when you explicitly mean both A and B, and you should use A and/or B when you mean A or B (or both).

In response to a request for pronunciation, I typically treat the / as a hyphen and simply say "and or". This is not always standard for the / symbol, however, and other words or phrases with a / may be different.

They have the same meaning. Catalogue is used in British English whereas catalog is mostly used in American English. I've also seen cases where catalogue was used by some American friends, though.