1/1 is an Half-time/Full-time betting market. It means the Home team is going to win at halftime and Fulltime. In other words, to win a 1/1 bet; By the end of the first half, the home team should be winning. By the end of the whole match (full-time), the home should be the winner.
Here, bet365 odds will show the return you can expect for a $1 bet. For instance, 2.50 odds will pay out $2.50 for every $1 you bet. Many international sports use this format, so it's worth understanding. bet365 Get a First Bet Safety Net up to $1,000 in Bonus Bets!