Why are runes powerful?

Could you please explain to me the reasons behind the profound power of runes? I'm quite fascinated by their mysterious nature and would like to delve deeper into their significance. Are they merely symbols with hidden meanings or do they possess some sort of inherent magical properties? If they indeed possess such power, how does it manifest and how can it be harnessed effectively? I'm eager to understand the intricacies of runes and why they are considered so powerful.