The vast majority of people experience at least 3 career changes during their working lives, and the pace may be picking up in the 21st century. Some career changes are voluntary, and some are involuntary. Both work for you, if you take the right approach and have the right mind set.
Career vs. Job
A "career" is your profession, and it hopefully has a "career path" with jobs of increasing responsibility and reward.
A career change is typically more significant than a job change. Hopefully, a career change leads to more meaningful and personally rewarding work for you. Although it may not always bring a greater salary, at least intially, it should bring greater satisfaction - so that Monday when you head back to work isn't the worst day of the week as it is for so many (the day that people in the USA typically have a heart attack, too).
A "job" is what you do every day.
For many of us, a job is not a "career" - it is "just a job." It pays the bills but it doesn't do much more for us.
For those of us who are incredibly lucky or who have paid attention to their own priorities and interests, a job is part of a career. Typically, we don't think of it as a job, when it is something we love to do. It is "my work" or "what I do."
Career Change vs. Job Change
Hopefully, when we make a voluntary or involuntary job change, we take the time to make sure the new job fits into our career path. If we don't, chances are good that we'll be in another job search sooner than we need to be because the job isn't a good fit. Which means we won't enjoy doing it, won't do it as well as we could, and may not be good enough at it to keep it for very long.
The best solution is to take the time to think about what you "really want to do when you grow up." If not now, when?
This section of Job-Hunt will hopefully help you with that transition from job to career, or from one career to another one, as times (and people) change.