All those who sew know the importance of over locking
If you want to quickly finish an edge of any type of fabric without folding, folding and sewing, or zig-zagging all of edges then consider buying a serger. It is a good investment, on a regular sewing machine it takes too much more time to do but serger can handle such tasks completely different and quicker. Let me put his way, if I had to pick between a sewing machine and a serger, I would have my vote for seger.
One can read a lot online reviews of machines, you can check out all different brands available in the market, etc. and you would find out that many other brands of sergers work just as well and have different features that people really like. If you have never seen one before or used a serger before, you can experience it and learn a bit more before buying. They all come with an instruction manual which are well written and easily understood. These books show series of drawings in colour to show the various seams and how they are formed, hemming options, and edge finishes. As one progress in his/her skills, the books offer many other options and techniques to use in creative ways.
If you are a beginner and somewhat afraid of using serger, books will get you past that fear and on to using machine quickly. It is recommended to keep a notebook with notes of stitch settings and samples of your work as you try each technique, keep it by your serger and sewing machine to refer to for inspiration, it is helpful when you refer back to it later and continue to add new samples to you workbook daily.