diff --git a/src/components/leftsidebar.js b/src/components/leftsidebar.js
new file mode 100644
index 00000000..3cb3f622
--- /dev/null
+++ b/src/components/leftsidebar.js
@@ -0,0 +1,81 @@
+import React from "react";
+import _ from "lodash";
+import Categorical from "./categorical/categorical";
+import Expression from "./expression/expression";
+import { connect } from "react-redux";
+import Heatmap from "./expression/diffExpHeatmap";
+import * as globals from "../globals";
+
+@connect((state) => {
+  return {
+
+  }
+})
+class LeftSideBar extends React.Component {
+  constructor(props) {
+    super(props);
+    this.state = {
+      currentTab: "metadata"
+    };
+  }
+  render() {
+    return (
+      <div style={{position: "fixed"}}>
+        <div style={{padding: 10}}>
+          <button
+            style={{
+              padding: "10px 30px",
+              outline: 0,
+              fontSize: 18,
+              fontStyle: this.state.currentTab === "metadata" ? "inherit" : "italic",
+              cursor: "pointer",
+              border: "none",
+              backgroundColor: "#FFF",
+              borderTop: this.state.currentTab === "metadata" ? "4px solid " + globals.brightBlue : "none",
+              borderBottom: this.state.currentTab === "metadata" ? "none" : "1px solid " + globals.lightGrey,
+              borderRight: this.state.currentTab === "metadata" ? "1px solid " + globals.lightGrey : "none",
+              borderLeft: this.state.currentTab === "metadata" ? "1px solid " + globals.lightGrey : "none",
+            }}
+            onClick={() => {this.setState({currentTab: "metadata"})}}>
+            Metadata
+          </button>
+          <button
+            style={{
+              padding: "10px 30px",
+              outline: 0,
+              fontSize: 18,
+              fontStyle: this.state.currentTab === "expression" ? "inherit" : "italic",
+              cursor: "pointer",
+              border: "none",
+              backgroundColor: "#FFF",
+              borderTop: this.state.currentTab === "expression" ? "4px solid " + globals.brightBlue : "none",
+              borderBottom: this.state.currentTab === "expression" ? "none" : "1px solid " + globals.lightGrey,
+              borderRight: this.state.currentTab === "expression" ? "1px solid " + globals.lightGrey : "none",
+              borderLeft: this.state.currentTab === "expression" ? "1px solid " + globals.lightGrey : "none",
+            }}
+            onClick={() => {this.setState({currentTab: "expression"})}}>
+            Expression
+          </button>
+        </div>
+        <div style={{
+          height: 500,
+          width: 350,
+          padding: 10,
+          overflowY: "scroll",
+          overflowX: "hidden",
+        }}>
+          {this.state.currentTab === "metadata" ? <Categorical/> : null}
+          {this.state.currentTab === "expression" ? <Heatmap/> : null}
+        </div>
+        <div style={{
+          boxShadow: "-3px -4px 13px 0px rgba(201,201,201,1)",
+          paddingTop: 10
+        }}>
+          <Expression/>
+        </div>
+      </div>
+    )
+  }
+};
+
+export default LeftSideBar;