Real-World Uses

Financial Analysis

Stock price moving average:
[100, 102, 101, 105, 103, 107]

20-day moving average:
[100, 102, 101] → avg 101
[102, 101, 105] → avg 102.67
[101, 105, 103] → avg 103
[105, 103, 107] → avg 105

Traders use this to spot trends!

Network Monitoring

Packet rate per second:
packets = [10, 15, 20, 18, 22, ...]

1-second window:
Current traffic: 22 packets/sec
Average: 17 packets/sec
Threshold: 25 packets/sec

Alert if threshold exceeded!

Anomaly Detection

Normal behavior window:
[5, 6, 4, 7, 5, 6]
avg = 5.5, std = 0.8

New window:
[5, 6, 4, 25, 5, 6]
avg = 8.5 - ANOMALY!

Flag unusual patterns!

User Analytics

Last 7 days of user activity:
Mon: 10 logins
Tue: 12
Wed: 11
Thu: 8
Fri: 9
Sat: 0 - Unusual!
Sun: 0

Rolling window shows pattern change

System Metrics

CPU usage monitoring:
Window = last 60 seconds

If average > 80%: Scale up
If average < 20%: Scale down

Sliding window prevents reaction to spikes

Video Streaming

Adaptive bitrate streaming:
Network: [5Mbps, 4Mbps, 6Mbps, 3Mbps, 5Mbps]

Average bandwidth (window = 5):
[5, 4, 6, 3, 5] → avg 4.6Mbps

Send 4.5Mbps video quality