the fastest half century in T20 was scored by Sanath Jayasuriy in 12 balls
Ajit Agarkar of India has scored the fastet half century in just 22 balls against zimbabwe in 1999
Brendon McCalen
Yuvaraj Singh
Robin Uthappa scored the first ever half century for India in twenty20 cricket, on 14 September 2007 against Pakistan.
Now it is Yuvraj Singh who scored fifty in just 12 balls. It is against England in recently concluded Twenty20 world cup,in 2007,at south Africa. Yuvraj hit 6 consecutive sixes in an over to complete his half century.
Sachin's debut first-class half-century came in his debut first-class match (he scored 100 not out) for Bombay against Gujarat on December 10 - 12, 1988.
Sachin Tendulkar has made most half centuries in Cricket World Cup. He has made 15 half centuries and he also holds the record of most centuries -6 centuries. He had played 45 matches and scored 2278 runs(which is also the most by any player)
Allan Border(63)
Yuvraj singh of the indian cricket team against england scored the half century of just 12 balls hitting six sixes of stuart braod's over and taking india to the victory he completly smashed broad all round the park and lter judged man of the match
Mehrab Hossain was the first Bangladeshi batsman to score a 50 in Cricket World Cup. He scored 64 against West Indies in 2009 world cup.
The first half-century by a Bangladesh player was scored by Azhar Hossain in the sixth One-Day International match in which they played.
Some significant milestones achieved in the world of half-century cricket include the introduction of limited-overs cricket in the 1960s, the first Cricket World Cup in 1975, the rise of T20 cricket in the 2000s, and the increasing popularity and commercialization of the sport globally.