I've heard of people taking a break for getting work experience or internships and jobs and so on ... is this the norm ?
I can't say if it's the norm, but I don't expect that working for a year or two after undergrad would be frowned upon by graduate admissions committees. So long as your job is related to your field of study, you'll be augmenting your academic studies with real-world experience, which can indeed be valuable in preparation for a graduate curriculum.
Personally, I applied for grad school straight out of undergrad, but didn't find the funding I was hoping for, so I worked for a year and then tried again. I received more and better offers the second time around.
I think the answer depends upon the field. Personally, I've known many people who work for a few years as technicians or other jobs before they decide they want to go to graduate school in the life sciences. I've also known people who could not get into the programs they wanted to they worked in research labs to build up their skill set.
This post on UC-Berkeley's also demonstrates that people often take some time between undergrad and grad school.
Also, some programs such as MBAs either require or strongly prefer applicants to have professional experience outside. This US News article talks about work experience expectations for MBA programs.