Ascending order means arranging numbers from smallest to largest. The numbers go up as you move from left to right.
It is also called increasing order. In Hindi it is बढ़ता क्रम.
Example: 18, 45, 126, 309, 872
18 is the smallest
872 is the largest
Each next number is bigger than the one before it
Another example with 3-digit numbers: 214, 356, 401, 589, 903
How to put numbers in ascending order:
Compare the numbers.
Pick the smallest and write it first.
From the remaining numbers, pick the next smallest.
Keep going until the largest number is last.
Opposite of this is descending order (घटता क्रम), which goes from largest to smallest: 903, 589, 401, 356, 214.