# 13-The Core Packages

其實不用自己克難的拼湊出程式的每個功能，在真實世界中，大多數的程式設計工作都是利用現有的函式庫。本章會探討一些 Go 常用的 packages。

一開始我們要先提醒大家：雖然這些函式庫的功能非常明確了（或是在前述章節介紹過了），不過 Go 語言引用的多數函式庫都需要特定領域的知識背景（例如：密碼學），這些技術都已經超出本書的討論範疇。


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