I'm guessing you don't know the context of the innings, which is what makes it great.
1999, Australia touring the West Indies, in Steve Waugh's first series as captain. Australia won the first test, thanks to Gillespie and McGrath knocking over the Windies for 51, and it appeared the series was heading for a farce. Lara made 213 in the second test though, and the West Indies won it and squared the series 1-1 with 2 to play.
In the third test, Australia made 490 and took a massive first innings lead of 161. Walsh took 5 though, and the West Indies were set 311 to win with the series on the line. After a good start, the Windies collapsed to 5/105 and it looked like Australia would win comfortably. Jimmy Adams held up one end though, and with Lara attacking at the other they added 133 for the 6th wicket. Adams got out with 73 still to get, and then McGrath got Jacobs and Perry in consecutive balls, and with 2 wickets in hand it looked like Australia would win again. Lara kept going though, while Ambrose survived 38 balls in a 54 run stand. When he got out, the West Indies still needed 9 more, and they got the last of them when Lara hit Gillespie through the covers to bring up his 150.
In all, the score was 9/311 in the 4th innings. Lara made 153 not out, the highest other score was 38, and only 3 other batsmen made it into double figures. This was on a 5th day pitch facing McGrath, Gillespie, Warne and MacGill, and the victory kept the series alive, though Australia won the 4th test to tie the series. It was simply one of the greatest innings ever.