diff --git a/builtin_cmd.c b/builtin_cmd.c
index 3ccf703556930d9aaf417821e0db99f59d1b310d..2db8ccd1a7ea8fab103e9d811800689e987db8e8 100644
--- a/builtin_cmd.c
+++ b/builtin_cmd.c
@@ -17,19 +17,19 @@ NX_IMPORT NX_Error PowerBoxBuiltinHelp(int argc, char *argv[], char * env);
 
 NX_PRIVATE PowerBoxCmd powerBoxCmdTable[] = 
 {
-    {"help", "print help info", PowerBoxBuiltinHelp},
-    {"cd", "change directory", PowerBoxBuiltinCd},
-    {"pwd", "print word direcotry", PowerBoxBuiltinPwd},
-    {"ls", "list files", PowerBoxBuiltinLs},
-    {"ps", "print state", PowerBoxBuiltinPs},
-    {"sleep", "sleep for a while", PowerBoxBuiltinSleep},
-    {"env", "print environment", PowerBoxBuiltinEnv},
-    {"echo", "echo string", PowerBoxBuiltinEcho},
-    {"hello", "print hello", PowerBoxBuiltinHello},
-    {"monitor", "pirnt monitor info", PowerBoxBuiltinMonitor},
-    {"time", "print current time", PowerBoxBuiltinTime},
-    {"signal", "send signal to process", PowerBoxBuiltinSignal},
-    {"start", "start a new application", PowerBoxBuiltinStart},
+    {"help", "print built-in commands", PowerBoxBuiltinHelp},
+    {"cd", "change working directory", PowerBoxBuiltinCd},
+    {"pwd", "print working directory", PowerBoxBuiltinPwd},
+    {"ls", "list directory contents", PowerBoxBuiltinLs},
+    {"ps", "print process status", PowerBoxBuiltinPs},
+    {"sleep", "delay for a specified time", PowerBoxBuiltinSleep},
+    {"env", "print environment variables", PowerBoxBuiltinEnv},
+    {"echo", "display a line of text", PowerBoxBuiltinEcho},
+    {"hello", "print hello world", PowerBoxBuiltinHello},
+    {"monitor", "print resource usage", PowerBoxBuiltinMonitor},
+    {"time", "print system date and time", PowerBoxBuiltinTime},
+    {"signal", "send signal to a specified process", PowerBoxBuiltinSignal},
+    {"start", "start a new process", PowerBoxBuiltinStart},
 };
 
 NX_PRIVATE void RunCmd(PowerBoxCmd *cmdInfo, char * cmd, char * env)
@@ -76,7 +76,7 @@ NX_Error PowerBoxPrintHelp(void)
     int i;
     PowerBoxCmd *cmdInfo;
 
-    NX_Printf("==== Build-in command for PowerBox ====\n");
+    NX_Printf("==== Built-in commands of PowerBox ====\n");
     for (i = 0; i < NX_ARRAY_SIZE(powerBoxCmdTable); i++)
     {
         cmdInfo = &powerBoxCmdTable[i];