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docs/en/guide/introduction.md

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+outline: deep
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+
+# What is lancet?
+
+<b>Lancet is a powerful, efficient, and reusable util function library of go. Inspired by the java apache common package and lodash.js. </b>
+
+
+## Why lancet?
+
+Lancet makes Go dev easier by taking the hassle out of working with concurrency, net, math, slice, string, etc.
+Lancet's utility methods are great for:
+
+- Iterating slice and  array.
+- Manipulating strings.
+- Work with net and http.
+- Other tools, eg. random, crypto, stream, retry, etc.