diff --git a/History.md b/History.md
index c3c609d..5db531f 100644
--- a/History.md
+++ b/History.md
@@ -16,7 +16,7 @@
 
 # 13.1.1 / 2017-10-07
 
-* Added missing return type for `.rejecteWith` in typescript definition
+* Added missing return type for `.rejectedWith` in typescript definition
 
 # 13.1.0 / 2017-09-20
 
@@ -86,7 +86,7 @@
 
 # 9.0.0 / 2016-05-30
 
-* Set should.config values to be more obvious. Pls check brecking changes page for exact values.
+* Set should.config values to be more obvious. Pls check breaking changes page for exact values.
 * Add support for SIMD data types.
 * Fixed minor bugs in .eql
 * Allow to show all equality check fails in .eql
@@ -180,7 +180,7 @@
 * **Breaking Change (possibly)** .matchEach and .matchAny now uses internally .match. See #65.
 * **Breaking Change** No more getter assertions. No all assertions are functions.
 * **Breaking Change** No more proxy returning, to check property names.
-* **Breaking Change** `should-format` now looks more like chrome developer tools inpections.
+* **Breaking Change** `should-format` now looks more like chrome developer tools inspections.
 
 # 6.0.3 / 2015-05-18
 
@@ -218,12 +218,12 @@
 * Remove old .eql implementation
 * Refactor nested errors
 * Added separate reporting message for false negative results like 10.should.not.equal(10)
-* Make error.message lazy fix old perfomance bottlenecks for constructing messages for big objects
+* Make error.message lazy fix old performance bottlenecks for constructing messages for big objects
 * Added .propertyWithDescriptor
 
 # 4.6.5 / 2015-02-05
 
-* Fix perfomance degradation on large objects
+* Fix performance degradation on large objects
 
 # 4.6.4 / 2015-02-05
 
diff --git a/Readme.md b/Readme.md
index c00feb4..3688432 100644
--- a/Readme.md
+++ b/Readme.md
@@ -188,10 +188,10 @@ AssertionError: expected { id: 10 } to be asset
 
 * [`should-sinon`](https://github.com/shouldjs/sinon) - adds additional assertions for sinon.js
 * [`should-immutable`](https://github.com/shouldjs/should-immutable) - extends different parts of should.js to make immutable.js first-class citizen in should.js
-* [`should-http`](https://github.com/shouldjs/http) - adds small assetions for assertion on http responses for node only
-* [`should-jq`](https://github.com/shouldjs/jq) - asserions for jq (need maintainer)
+* [`should-http`](https://github.com/shouldjs/http) - adds small assertions for assertion on http responses for node only
+* [`should-jq`](https://github.com/shouldjs/jq) - assertions for jq (need maintainer)
 * [`karma-should`](https://github.com/seegno/karma-should) - make more or less easy to work karma with should.js
-* [`should-spies`](https://github.com/shouldjs/spies) - small and dirty simple zero dependcies spies
+* [`should-spies`](https://github.com/shouldjs/spies) - small and dirty simple zero dependencies spies
 
 
 ## Contributions
diff --git a/lib/assertion.js b/lib/assertion.js
index c81c9c2..d73300d 100644
--- a/lib/assertion.js
+++ b/lib/assertion.js
@@ -54,7 +54,7 @@ Assertion.prototype = {
    * Before calling this method need to fill Assertion#params object. This method usually called from other assertion methods.
    * `Assertion#params` can contain such properties:
    * * `operator` - required string containing description of this assertion
-   * * `obj` - optional replacement for this.obj, it usefull if you prepare more clear object then given
+   * * `obj` - optional replacement for this.obj, it is useful if you prepare more clear object then given
    * * `message` - if this property filled with string any others will be ignored and this one used as assertion message
    * * `expected` - any object used when you need to assert relation between given object and expected. Like given == expected (== is a relation)
    * * `details` - additional string with details to generated message
diff --git a/should.d.ts b/should.d.ts
index c320bb5..47678f8 100644
--- a/should.d.ts
+++ b/should.d.ts
@@ -9,7 +9,7 @@ declare function should(obj: any): should.Assertion;
   equal(actual: any, expected: any, message?: string): void;
   notEqual(actual: any, expected: any, message?: string): void;
   deepEqual(actual: any, expected: any, message?: string): void;
-  notDeepEqual(acutal: any, expected: any, message?: string): void;
+  notDeepEqual(actual: any, expected: any, message?: string): void;
   strictEqual(actual: any, expected: any, message?: string): void;
   notStrictEqual(actual: any, expected: any, message?: string): void;
 
@@ -43,7 +43,7 @@ declare namespace should {
   function equal(actual: any, expected: any, message?: string): void;
   function notEqual(actual: any, expected: any, message?: string): void;
   function deepEqual(actual: any, expected: any, message?: string): void;
-  function notDeepEqual(acutal: any, expected: any, message?: string): void;
+  function notDeepEqual(actual: any, expected: any, message?: string): void;
   function strictEqual(actual: any, expected: any, message?: string): void;
   function notStrictEqual(actual: any, expected: any, message?: string): void;
 
@@ -119,7 +119,7 @@ declare namespace should {
     throw(): this;
     throw(msg: RegExp | string | Function, properties?: {}): this;
     throw(properties: {}): this;
-    //TODO how to expess generators???
+    //TODO how to express generators???
     throwError(): this;
     throwError(msg: RegExp | string | Function, properties?: {}): this;
     throwError(properties: {}): this;
diff --git a/should.js b/should.js
index 572ff4f..78ef259 100644
--- a/should.js
+++ b/should.js
@@ -134,15 +134,15 @@ TypeChecker.prototype = {
   },
 
   addTypeOf: function(type, res) {
-    return this.add(function(obj, tpeOf) {
-      if (tpeOf === type) {
+    return this.add(function(obj, typeOf) {
+      if (typeOf === type) {
         return new Type(res);
       }
     });
   },
 
   addClass: function(cls, res, sub) {
-    return this.add(function(obj, tpeOf, objCls) {
+    return this.add(function(obj, typeOf, objCls) {
       if (objCls === cls) {
         return new Type(types.OBJECT, res, sub);
       }
@@ -241,7 +241,7 @@ main
     }
   })
   .add(function(obj) {
-    // probably at the begginging should be enough these checks
+    // probably at the beginning should be enough these checks
     if (obj.Boolean === Boolean && obj.Number === Number && obj.String === String && obj.Date === Date) {
       return new Type(types.OBJECT, types.HOST);
     }
@@ -1612,7 +1612,7 @@ Assertion.prototype = {
    * Before calling this method need to fill Assertion#params object. This method usually called from other assertion methods.
    * `Assertion#params` can contain such properties:
    * * `operator` - required string containing description of this assertion
-   * * `obj` - optional replacement for this.obj, it usefull if you prepare more clear object then given
+   * * `obj` - optional replacement for this.obj, it is useful if you prepare more clear object then given
    * * `message` - if this property filled with string any others will be ignored and this one used as assertion message
    * * `expected` - any object used when you need to assert relation between given object and expected. Like given == expected (== is a relation)
    * * `details` - additional string with details to generated message