Does "use X, Y, or Z" mean use *one of* or *all of* the options?

Question

This is the text supposedly providing the parameters for creating acceptable usernames for a particular website:

The username is case sensitive. Choose a username that is 6-74 characters long and must contain a lowercase or capital letter, a number, or one of these symbols _.@/-

In other words: A username for this site must consist of from 6 to 74 characters and must contain one of the following:

 -any upper or lower case letter
 -any 6 to 74 digit number 
 -any one of the following symbols _.@/-

Therefore, any of the following should be acceptable usernames:

• @@@@@@
• 99999999999999999999999999999999999
• /////......///
• dar2zen

None of those, however, are actually accepted by the website. Therefore, the parameters, as stated, do not state what they mean to state. What they do mean to state is not clear. When the system rejects a username, no feedback on what requirement that username is failing to meet is given.

My question here is whether I am correct in believing that the username requirements, as written, state what I say they state.

Answer 1

As written the instructions are rather unclear. The more appropriate way to write out these kinds of complicated instructions is to use a list of requirements:

The username is case sensitive. Choose a username that satisfies each of the following requirements:

• 6-74 characters long
• contains at least one letter
• contains at least one number
• contains at least one of these symbols _.@/-

To answer your specific question, the paragraph is written as these instructions are often written and does explain the requirements but it does not do so unambiguously.

In short:

1. The paragraph is not strictly, technically correct (e.g. @@@@@@ is not a valid username)
2. The paragraph's actual meaning is clear in the sense that they convey the intended rules in plain English (albeit poorly) because users don't typically try to create usernames like @@@@@@ legitimately
3. The website should update their paragraph to be both technically correct (1) and convey the meaning in English (2)

Answer 2

"or" means 'or". As written any one of those categories would be valid, so:

"000000000"

should be a valid password.

Since it is not, the definitions of the requirements of a password remains incomplete.

Apparently the commenters seem to be converging that the true rules are:

6 characters+ which can be letters, numbers and punctuation.

Must contain three of the following: small letters, capital letters, numbers, and punctuation.

Answer 3

Yes, it is correct. The question says or, so it basically gives you a choice between them.