Latency facts for kids

In engineering, latency is the time it takes for something to happen after you ask it to. Think of it as a waiting period. For example, when you click a button on a website, the time it takes for the page to load is a type of latency.

What is Latency?

Latency is a delay. It's the time between a cause and its effect. Imagine you send a message to a friend. The time it takes for your friend to receive that message is latency. In computers and technology, latency is super important. It affects how fast things feel and work.

Latency in Everyday Life

You experience latency all the time, even if you don't call it that.

• Video games: When you press a button to make your character jump, the delay until they actually jump is latency. High latency (or "lag") makes games hard to play.
• Internet: When you click a link, the time it takes for the website to appear is network latency. This depends on how far away the website's server is and how busy the internet lines are.
• Phone calls: If you're talking to someone far away, there might be a tiny delay between when you speak and when they hear you. That's audio latency.
• Traffic lights: The time between the light turning green and the first car moving is also a form of latency in a system.

Why Latency Matters

Low latency is usually better. It means things happen quickly and smoothly.

• Faster internet: Less waiting for pages to load or videos to start.
• Better gaming: No frustrating delays between your actions and what happens on screen.
• Smooth video calls: Conversations feel more natural without awkward pauses.
• Self-driving cars: Very low latency is critical for safety. The car needs to react instantly to changes on the road.

How Latency is Measured

Latency is measured in units of time.

• Milliseconds (ms): This is the most common unit. One millisecond is one-thousandth of a second.
• Seconds (s): For very long delays, seconds might be used.

For example, a good internet connection might have a latency of 20-50 ms when connecting to a nearby server. If it's 200 ms or more, you'll start to notice delays.

Types of Latency

Latency can happen in different parts of a system.

• Network latency: The time it takes for data to travel across a network, like the internet.
• Disk latency: The time it takes for a computer's hard drive to find and read data.
• Processing latency: The time it takes for a computer's processor to complete a task.
• Sensor latency: The time it takes for a sensor (like in a self-driving car) to detect something and send the information.

All these different types of delays add up to the total latency you experience. Engineers work hard to reduce latency in all kinds of systems to make technology faster and more efficient.

Images for kids

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  A robot representing technology where latency is important.