The term "member" as it applies to an LLC is synonymous to the term "shareholder" as it applies to a corporation. But both corporations and LLC's are also allowed to have "employees" and "officers." If your LLC articles state that you are manager managed, then you will also have one or more "managers". Or in the case of a single member, they might state that the single member has the sole right to manage, which effectively makes them a "manager" as well.
So, right off the bat in a single member manager managed LLC, you are both a "member", a "manager", and the "owner" since you hold all the membership.
Like I said, LLC's can also have "officers" and those officers can also be "members". Though it would be silly to appoint yourself as one or more officers and use that title in your every day activity, they're usually just used for legal and/or tax purposes. You usually (or should) document appointing officers with an appointment resolution, which is just a basic document that lists the title, person's name, and compensation [if any] for serving the officer's position.
For example, I am a member in a few LLCs. In one, I am also an officer, the CTO, but I don't use that title in my day to day activities [even though it is a fairly accurate description]. It is only for legal papers and taxes that it is used.
For anyone with Nolo's LLC Operating Manual, I'll refer you to chapter/page 12/8:
State LLC laws usually allow an LLC to appoint whatever officers it decides are necessary or convenient to carry out its business. Typically, an LLC has a president, a treasurer, and a secretary, plus any additional officer positions it decides to fill. In a small one- or two-owner LLC, one person might hold more than one officer position. State law typically allows this. In many instances, officer titles such as president and secretary are formal, administrative titles only. They are used by the officer only when signing legal or approving LLC legal or tax papers. In other words, even though a person may be granted the title of LLC president or treasurer, he or she is typically paid a salary in connection with other full-time work for the LLC.
So again for example, I also have my own single member manager managed LLC. I am also appointed to fill the officer positions of president and treasurer. But I don't use these titles. They're just formal, and I only use them or identity myself as that officer when it is necessary to in paperwork. When necessary to identify my title in day to day activity, I use "owner".
People in small businesses usually wear many hats, and small LLCs are no different here