diff --git a/cmd/mcping/mcping.go b/cmd/mcping/mcping.go
index 5686aac..a74ca6a 100644
--- a/cmd/mcping/mcping.go
+++ b/cmd/mcping/mcping.go
@@ -1,4 +1,4 @@
-// Useage: go run cmd/ping/ping.go localhost
+// Usage: go run cmd/ping/ping.go localhost
 package main
 
 import (
diff --git a/cmd/substitute_server/substitute.go b/cmd/substitute_server/substitute.go
index 4ee0366..e0a9df9 100644
--- a/cmd/substitute_server/substitute.go
+++ b/cmd/substitute_server/substitute.go
@@ -225,8 +225,8 @@ func getStatus() pk.Packet {
 	}
 }
 
-func disconnectID(protocal int32) byte {
-	switch protocal {
+func disconnectID(protocol int32) byte {
+	switch protocol {
 	case 404:
 		return 0x1B
 	case 477, 480:
diff --git a/net/packet/types.go b/net/packet/types.go
index 86edbbb..d5cbba1 100644
--- a/net/packet/types.go
+++ b/net/packet/types.go
@@ -13,12 +13,12 @@ type Field interface {
 	FieldDecoder
 }
 
-// A FieldEncoder can be encode as minecraft protocal used.
+// A FieldEncoder can be encode as minecraft protocol used.
 type FieldEncoder interface {
 	Encode() []byte
 }
 
-// A FieldDecoder can Decode from minecraft protocal
+// A FieldDecoder can Decode from minecraft protocol
 type FieldDecoder interface {
 	Decode(r DecodeReader) error
 }