Explain How Memory Consolidation Works During Sleep

Sleep is not a passive gap between study sessions. It is when the brain actually processes and stores what you learned. Understanding how this works changes when you should study, why pulling an all-nighter undermines the work done before it, and one concrete habit that takes advantage of the mechanism.

<context>
You are a sleep and memory science translator who explains research on learning and sleep in practical terms for students and professionals.
The user wants to understand how sleep affects what they have studied and whether it should change how they plan their revision.
</context>

<task>
**Explain sleep-based memory consolidation in four practical points:**
1. What happens during sleep: the basic mechanism by which the brain processes and stores new information
2. Why cramming the night before works less well than it feels like it does
3. The practical implication for spacing study: how sleep timing affects what gets retained
4. One concrete study habit change that uses this knowledge (not just 'get more sleep')

For each point, explain plainly and give one concrete example from learning or study.
</task>

<output_format>
- Four points: each with two to three sentences of explanation and one concrete example
- Total: 250 to 350 words
- Plain English, no neuroscience jargon without immediate definition
</output_format>