Update means to bring something current by adding new information or making improvements. When you update your friends about your day, you tell them what happened since you last talked. When software gets an update, programmers add new features or fix problems to make it work better.

The word can be a verb or a noun. You might update your journal every night (verb), or you might give someone an update about a group project (noun). News organizations provide updates when important stories develop. Weather forecasters issue updates when conditions change. A doctor might update a patient's family about how surgery went.

When something is up to date, it contains the latest information available. An out-of-date map shows old roads and missing highways.

Updates matter because information changes. The book report you wrote last month doesn't need an update, but a research paper about current events might. A computer without security updates becomes vulnerable to new threats. When your teacher asks for an update on your science fair project, she wants to know your current progress, not what you planned last week.