This is the 6687th most frequent Japanese word.
ハード
"Hard" or "difficult."
Here, ハード is used as an adjective to describe the intensity or toughness of the training.
彼のトレーニングはとてもハードで厳しい。
His training is very hard and strict.
Here, ハード is used to describe the difficulty level of operating the program.
このプログラムの操作はハードです。
The operation of this program is hard.
Here, ハード refers to hardware, which is a common usage as a noun.