The focal distances SP = a - ex1 and SP' = a + ex1 sum to 2a. For a focal chord (chord through a focus), the endpoints have eccentric angles satisfying tan(alpha/2)tan(beta/2) = (e-1)/(e+1). The minimum focal chord is the latus rectum = 2b^2/a, occurring when the chord is perpendicular to the major axis. The harmonic mean of the two focal segment lengths equals the semi-latus rectum b^2/a. The circle on a focal chord as diameter touches the corresponding directrix. If d1 and d2 are perpendicular distances from foci to any tangent, then d1d2 = b^2. The segment TG (tangent and normal meet the axis at T and G) subtends a right angle at either focus. These focal properties are the most frequently tested in JEE, especially SP + SP' = 2a.