Your sexual orientation means the general attraction you feel towards people of one sex or another (or both). Most people are generally attracted to:
Same-sex attraction is called homosexuality. On this site, we call men and women who are homosexual either ‘gay’ (for men) or ‘lesbian’ (for women).
Opposite-sex attraction is called heterosexuality. On this site, we describe people who are heterosexual as ‘straight’.
Both-sex attraction is called bisexuality. On this site, we use the word ‘bisexual’, or occasionally just ‘bi’, to describe people who are attracted to both sexes.