This letter is a "S" or a "SH" sound. When this letter has the horizontal lines on the top, the letter becomes stressed more and is sometimes a sort of T sound. The standard "T" letter is the one that looks like a C or an E. The letter that looks like C is often in between "D" and "T" sound, while the letter like E (having a stress mark notch) is much more of a "T" This is from what I understand. I am just learning Korean myself, so it might be somewhat inaccurate, but I think I said it right.