The image of the rainbow has become the modern symbol for gay or homosexual pride and activism. This is a good example of how a symbol can have applied meaning throughout the world and within culture who create them and give them meaning. Symbols like these are also found within religious scripture and culture, for the same purpose.
Some have the idea that to practice magic, you have to be particularly talented, or have spent decades honing the craft. In truth, magic is a lot like water. We all have it, but we must spend time purifying it. That said, sigils are an easy way for magic to be practiced, even for the most mundane of us.