Finished for now - more information in the body!

New behaviour for 0 division, now multiple operations can be executed without pressing equals every operation, floating math reduced to 5, added using checks for numbers

script.js

@@ -15,6 +15,9 @@ function multiply(a, b) {
 }
 
 function divide(a, b) {
+    if (b == 0) {
+        return "Dividing by 0? That's illegal!";
+    }
     return a / b;
 }
 
@@ -113,6 +116,11 @@ function handleOperators(value) {
     if (operation.addToA) {
         operation.operator = value;
     }
+    if (operation.readyForEquasion) {
+        execute(operation);
+        operation.addToA = !operation.addToA;
+        operation.operator = value;
+    }
     operation.outputOfEquasion = false;
 }
 
@@ -135,12 +143,20 @@ function clear() {
     valueGui.textContent = operation.a;
 }
 
-function populateDisplay(operation) {
+function display(operation) {
     signGui.textContent = `${operation.operator}`;
     if (operation.displayA) {
-        valueGui.textContent = `${operation.a}`;
+        if (operation.a[operation.a.length - 1] == ".") {
+            valueGui.textContent = `${operation.a}`;
+        } else {
+            valueGui.textContent = `${Math.round(parseFloat(operation.a) * 100000) / 100000}`;
+        }
     } else {        
-        valueGui.textContent = `${operation.b}`;
+        if (operation.b[operation.b.length - 1] == ".") {
+            valueGui.textContent = `${operation.b}`;
+        } else {
+            valueGui.textContent = `${Math.round(parseFloat(operation.b) * 100000) / 100000}`;
+        }
     }
 }
 
@@ -154,6 +170,9 @@ function handleAction(e) {
     }
     let action = true;
     let passLetter = e.key.toLowerCase();
+    if (!checkNumber(operation.a) || !checkNumber(operation.b)) {
+        clear();
+    }
     if (passLetter == " "
      || passLetter == ".") {
         addPoint();
@@ -177,7 +196,8 @@ function handleAction(e) {
         action = false;
     }
     if (action) {
-        populateDisplay(operation);
+        display(operation);
+        e.preventDefault();
     };
 }