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docs/en/guide/getting_started.md

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+---
+outline: deep
+---
+
+# Installation
+
+1. <b>For users who use go1.18 and above, it is recommended to install lancet v2.x.x. Cause in v2.x.x all functions was rewriten with generics of go1.18.</b>
+
+```go
+go get github.com/duke-git/lancet/v2 // will install latest version of v2.x.x
+```
+
+2. <b>For users who use version below go1.18, you should install v1.x.x. The latest of v1.x.x is v1.4.1. </b>
+
+```go
+go get github.com/duke-git/lancet // below go1.18, install latest version of v1.x.x
+```
+
+
+## Usage
+
+Lancet organizes the code into package structure, and you need to import the corresponding package name when use it. For example, if you use string-related functions, just import the strutil package like below:
+
+```go
+import "github.com/duke-git/lancet/v2/strutil"
+```
+
+## Example
+
+Here takes the string function `Reverse` (reverse order string) as an example, and the strutil package needs to be imported.
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/strutil"
+)
+
+func main() {
+    s := "hello"
+    rs := strutil.Reverse(s)
+    fmt.Println(rs) //olleh
+}
+```
+
+
+## More
+
+Check out the [APIs]([API](https://lancet.go.dev/api/overview.html)) for details.