What is Standard Deviation? Introduction In mathematics and data analysis, we often want to understand how spread out values are. Standard deviation is one of the most important concepts used to measure this spread. It is widely used in statistics, data science, and machine learning. What is Standard Deviation? Standard deviation tells us how much the values in a dataset differ from the average (mean). 👉 In simple words: It shows whether data is close to the mean or spread far away . Formula of Standard Deviation Where: x = each value μ = mean N = total number of values Step-by-Step Example Let’s take a simple dataset: 👉 2, 4, 6, 8, 10 Step 1: Find Mean Mean = (2 + 4 + 6 + 8 + 10) / 5 = 6 Step 2: Subtract Mean from each value (2−6), (4−6), (6−6), (8−6), (10−6) = −4, −2, 0, 2, 4 Step 3: Square the values 16, 4, 0, 4, 16 Step 4: Find average of squared values (16 + 4 + 0 + 4 + 16) / 5 = 8 Step 5: Square root Standard deviation = √8 ≈ 2.83 Interpretat...