How can you use an ace in Texas Holdem?

Can you elaborate on the strategic usage of an ace in Texas Holdem? How does its presence influence your decision-making during preflop, flop, turn, and river? How does the position of the ace in your hand, such as a pair of aces or an ace-high flush draw, alter your playstyle? Additionally, how do you adjust your strategy when facing opponents who might be aware of your potential strong hand?