Explain list comprehension in Python with examples

List comprehension is a concise way to create lists.

```python
# Traditional way
squares = []
for x in range(10):
squares.append(x**2)

# List comprehension
squares = [x**2 for x in range(10)]

# With condition
evens = [x for x in range(20) if x % 2 == 0]
```

Faster and more readable than traditional loops.