diff --git a/README.md b/README.md
index 9b4dadf..32a51c6 100644
--- a/README.md
+++ b/README.md
@@ -2,6 +2,11 @@
 
 Get the resistor, capacitor, or inductor circuit which has the closest value for your given value within at most 3 devices.
 
+This project is coming from HFUT experiment class where I need to build an active low-pass filter with limited laboratory components.
+So I create this project to help me to find the closest circuit for my given value.
+After a couple of years, I still find it useful, so I decide to refactor it.
+And make it available for everyone in a more convenient way, like GUI and mobile app.
+
 # Todos
 
 - [x] Refactor the legacy version.