diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index d40da256..d43b8240 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -25,6 +25,7 @@ César Cará <cesar.cara@protonmail.com>
 Cheikh Seck <cheikh.seck@ardanlabs.com>
 Gustavo Castillo <gcdcoder@gmail.com>
 Hana Mohan <hana@magicbell.io>
+Oleksandr Redko <oleksandr.red+ardanlabs@gmail.com>
 Sergey Kibish <5479211+skibish@users.noreply.github.com>
 Todd McLeod <8296040+GoesToEleven@users.noreply.github.com>
 Wendel Castro <wendel.castro@ardanlabs.com>
diff --git a/README.md b/README.md
index f8f90ffa..e9e9688e 100644
--- a/README.md
+++ b/README.md
@@ -36,7 +36,7 @@ There is a book for all of the material in the class.
 
 We have taught Go to thousands of developers all around the world since 2014. There is no other company that has been doing it longer and our material has proven to help jump-start developers 6 to 12 months ahead of their knowledge of Go. We know what knowledge developers need in order to be productive and efficient when writing software in Go.
 
-Our classes are perfect for intermediate-level developers who have at least a few months to years of experience writing code in Go. Our classes provide a very deep knowledge of the programming langauge with a big push on language mechanics, design philosophies and guidelines. We focus on teaching how to write code with a priority on consistency, integrity, readability and simplicity. We cover a lot about “if performance matters” with a focus on mechanical sympathy, data oriented design, decoupling and writing/debugging production software.
+Our classes are perfect for intermediate-level developers who have at least a few months to years of experience writing code in Go. Our classes provide a very deep knowledge of the programming language with a big push on language mechanics, design philosophies and guidelines. We focus on teaching how to write code with a priority on consistency, integrity, readability and simplicity. We cover a lot about “if performance matters” with a focus on mechanical sympathy, data oriented design, decoupling and writing/debugging production software.
 
 ## Our Teachers
 
@@ -138,10 +138,10 @@ Please check out this page of [important reading](https://github.com/ardanlabs/g
 
 ## Joining the Go Slack Community
 
-We use a slack channel to share links, code, and examples during the training.  This is free.  This is also the same slack community you will use after training to ask for help and interact with may Go experts around the world in the community.
+We use a Slack channel to share links, code, and examples during the training.  This is free.  This is also the same Slack community you will use after training to ask for help and interact with may Go experts around the world in the community.
 
 * Using the following link, fill out your name and email address: https://invite.slack.gobridge.org/
-* Check your email, and follow the link to the slack application.
+* Check your email, and follow the link to the Slack application.
 
 ___
 All material is licensed under the [Apache License Version 2.0, January 2004](http://www.apache.org/licenses/LICENSE-2.0).
\ No newline at end of file
diff --git a/_content/tour/eng/algorithms/sorting/insertion.go b/_content/tour/eng/algorithms/sorting/insertion.go
index 665a4a75..798c6416 100644
--- a/_content/tour/eng/algorithms/sorting/insertion.go
+++ b/_content/tour/eng/algorithms/sorting/insertion.go
@@ -25,7 +25,7 @@ func insertionSort(numbers []int) {
 	// Walk through the numbers from left to right. Through
 	// each outer loop iteration we move values from right
 	// to left inside the array when they are larger than
-	// the value that preceed it.
+	// the value that precedes it.
 
 	for i := 1; i < n; i++ {
 		j := i
diff --git a/_content/tour/eng/generics/multi-type-params/example1.go b/_content/tour/eng/generics/multi-type-params/example1.go
index 87ca2d31..5e9f13e3 100644
--- a/_content/tour/eng/generics/multi-type-params/example1.go
+++ b/_content/tour/eng/generics/multi-type-params/example1.go
@@ -3,7 +3,7 @@
 // All material is licensed under the Apache License Version 2.0, January 2004
 // http://www.apache.org/licenses/LICENSE-2.0
 
-// Sample program to show how to write a generic functions tha take multiple
+// Sample program to show how to write a generic functions that take multiple
 // generic parameters.
 package main
 
diff --git a/_content/tour/eng/variables.article b/_content/tour/eng/variables.article
index b2d2ec40..66d9d7f3 100644
--- a/_content/tour/eng/variables.article
+++ b/_content/tour/eng/variables.article
@@ -27,7 +27,7 @@ Types can be specific to a precision such as int32 or int64:
 
 - uint8 represents an unsigned integer with 1 byte of allocation
 - int32 represents a signed integer with 4 bytes of allocation. When you declare a type
-using a non-precision based type (unit, int) the size of the value is based on the
+using a non-precision based type (uint, int) the size of the value is based on the
 architecture being used to build the program:
 
 - 32 bit arch: int represents a signed int at 4 bytes of memory allocation
diff --git a/_content/tour/fre/algorithms/sorting/insertion.go b/_content/tour/fre/algorithms/sorting/insertion.go
index 665a4a75..798c6416 100644
--- a/_content/tour/fre/algorithms/sorting/insertion.go
+++ b/_content/tour/fre/algorithms/sorting/insertion.go
@@ -25,7 +25,7 @@ func insertionSort(numbers []int) {
 	// Walk through the numbers from left to right. Through
 	// each outer loop iteration we move values from right
 	// to left inside the array when they are larger than
-	// the value that preceed it.
+	// the value that precedes it.
 
 	for i := 1; i < n; i++ {
 		j := i
diff --git a/_content/tour/fre/generics/multi-type-params/example1.go b/_content/tour/fre/generics/multi-type-params/example1.go
index 87ca2d31..5e9f13e3 100644
--- a/_content/tour/fre/generics/multi-type-params/example1.go
+++ b/_content/tour/fre/generics/multi-type-params/example1.go
@@ -3,7 +3,7 @@
 // All material is licensed under the Apache License Version 2.0, January 2004
 // http://www.apache.org/licenses/LICENSE-2.0
 
-// Sample program to show how to write a generic functions tha take multiple
+// Sample program to show how to write a generic functions that take multiple
 // generic parameters.
 package main
 
diff --git a/_content/tour/fre/variables.article b/_content/tour/fre/variables.article
index 990eec3b..133128e5 100644
--- a/_content/tour/fre/variables.article
+++ b/_content/tour/fre/variables.article
@@ -23,7 +23,7 @@ Que représente cette mémoire ? (par exemple : int, uint, bool...)
 Les types peuvent spécifier une précision telle que `int32` ou `int64` :
 
 - uint8 représente un entier non signé avec une allocation mémoire de 1 octet.
-- int32 représente un entier signé avec une allocation mémoire de 4 octets. Lorsque vous déclarez un type en utilisant un type dont la précision n'est pas spécifiée (unit, int), la taille de la valeur est basée sur l'architecture utilisée pour construire le programme :
+- int32 représente un entier signé avec une allocation mémoire de 4 octets. Lorsque vous déclarez un type en utilisant un type dont la précision n'est pas spécifiée (uint, int), la taille de la valeur est basée sur l'architecture utilisée pour construire le programme :
 
 - 32 bit arch : int représente un int signé avec 4 octets d'allocation mémoire
 - 64 bits : int représente un int signé à 8 octets d'allocation de mémoire
diff --git a/_content/tour/ger/algorithms/sorting/insertion.go b/_content/tour/ger/algorithms/sorting/insertion.go
index 665a4a75..798c6416 100644
--- a/_content/tour/ger/algorithms/sorting/insertion.go
+++ b/_content/tour/ger/algorithms/sorting/insertion.go
@@ -25,7 +25,7 @@ func insertionSort(numbers []int) {
 	// Walk through the numbers from left to right. Through
 	// each outer loop iteration we move values from right
 	// to left inside the array when they are larger than
-	// the value that preceed it.
+	// the value that precedes it.
 
 	for i := 1; i < n; i++ {
 		j := i
diff --git a/_content/tour/ger/generics/multi-type-params/example1.go b/_content/tour/ger/generics/multi-type-params/example1.go
index 87ca2d31..5e9f13e3 100644
--- a/_content/tour/ger/generics/multi-type-params/example1.go
+++ b/_content/tour/ger/generics/multi-type-params/example1.go
@@ -3,7 +3,7 @@
 // All material is licensed under the Apache License Version 2.0, January 2004
 // http://www.apache.org/licenses/LICENSE-2.0
 
-// Sample program to show how to write a generic functions tha take multiple
+// Sample program to show how to write a generic functions that take multiple
 // generic parameters.
 package main
 
diff --git a/_content/tour/ger/variables.article b/_content/tour/ger/variables.article
index 53629538..c92d6d17 100644
--- a/_content/tour/ger/variables.article
+++ b/_content/tour/ger/variables.article
@@ -27,7 +27,7 @@ Typen können spezifisch für eine Genauigkeit wie int32 oder int64 sein:
 - uint8 steht für eine ganze Zahl ohne Vorzeichen mit einer Zuweisung von 1 Byte
 - int32 steht für eine ganze Zahl mit Vorzeichen und 4 Byte Zuweisung. 
 
-Wenn ihr einen Typen mit einem nicht-präzisionsbasierten Typen (unit, int) deklariert, richtet sich die Größe des Wertes nach der
+Wenn ihr einen Typen mit einem nicht-präzisionsbasierten Typen (uint, int) deklariert, richtet sich die Größe des Wertes nach der
 Architektur, die für die Erstellung des Programms verwendet wird:
 
 - 32-Bit-Bogen: int stellt einen vorzeichenbehafteten int mit 4 Byte Speicherzuweisung dar
diff --git a/_content/tour/grc/variables.article b/_content/tour/grc/variables.article
index 72dce3ee..b1feeda3 100644
--- a/_content/tour/grc/variables.article
+++ b/_content/tour/grc/variables.article
@@ -30,7 +30,7 @@
 - ο int32 αναπαριστά έναν ακέραιο αριθμό, δεσμεύοντας 4 byte μνήμης. 
 
 Όταν ορίζετε ένα τύπο μεταβλητών 
-χρησιμοποιώντας κάποιον άλλο τύπο χωρίς αριθμητική ακρίβεια (unit, int), το μέγεθος της τιμής μιας μεταβλητής αυτού του τύπου, βασίζεται 
+χρησιμοποιώντας κάποιον άλλο τύπο χωρίς αριθμητική ακρίβεια (uint, int), το μέγεθος της τιμής μιας μεταβλητής αυτού του τύπου, βασίζεται 
 στην αρχιτεκτονική που χρησιμοποιείται για την δημιουργία του προγράμματος:
 
 - στην αρχιτεκτονική 32 bit: ο int αναπαριστά έναν ακέραιο δεσμεύοντας 4 byte μνήμης
diff --git a/_content/tour/ita/algorithms/sorting/insertion.go b/_content/tour/ita/algorithms/sorting/insertion.go
index 665a4a75..798c6416 100644
--- a/_content/tour/ita/algorithms/sorting/insertion.go
+++ b/_content/tour/ita/algorithms/sorting/insertion.go
@@ -25,7 +25,7 @@ func insertionSort(numbers []int) {
 	// Walk through the numbers from left to right. Through
 	// each outer loop iteration we move values from right
 	// to left inside the array when they are larger than
-	// the value that preceed it.
+	// the value that precedes it.
 
 	for i := 1; i < n; i++ {
 		j := i
diff --git a/_content/tour/ita/generics/multi-type-params/example1.go b/_content/tour/ita/generics/multi-type-params/example1.go
index 87ca2d31..5e9f13e3 100644
--- a/_content/tour/ita/generics/multi-type-params/example1.go
+++ b/_content/tour/ita/generics/multi-type-params/example1.go
@@ -3,7 +3,7 @@
 // All material is licensed under the Apache License Version 2.0, January 2004
 // http://www.apache.org/licenses/LICENSE-2.0
 
-// Sample program to show how to write a generic functions tha take multiple
+// Sample program to show how to write a generic functions that take multiple
 // generic parameters.
 package main
 
diff --git a/_content/tour/ita/variables.article b/_content/tour/ita/variables.article
index bb1be728..58692006 100644
--- a/_content/tour/ita/variables.article
+++ b/_content/tour/ita/variables.article
@@ -26,7 +26,7 @@ I tipi possono essere specifici sulla precisione come int32 o int64::
 
 - uint8 rappresenta un intero senza segno con 1 byte di allocazione
 - int32 rappresenta un intero con segno con 4 bytes di allocazione. Quando dichiari un tipo
-usando un tipo senza precisione (unit, int) la dimensione del valore è basata
+usando un tipo senza precisione (uint, int) la dimensione del valore è basata
 sulla architettura usata per compilare il programma:
 
 - Architettura 32 bit : int rappresenta un int con segno a 4 bytes di allocazione di memoria
diff --git a/_content/tour/per/algorithms/sorting/insertion.go b/_content/tour/per/algorithms/sorting/insertion.go
index 665a4a75..798c6416 100644
--- a/_content/tour/per/algorithms/sorting/insertion.go
+++ b/_content/tour/per/algorithms/sorting/insertion.go
@@ -25,7 +25,7 @@ func insertionSort(numbers []int) {
 	// Walk through the numbers from left to right. Through
 	// each outer loop iteration we move values from right
 	// to left inside the array when they are larger than
-	// the value that preceed it.
+	// the value that precedes it.
 
 	for i := 1; i < n; i++ {
 		j := i
diff --git a/_content/tour/per/generics/multi-type-params/example1.go b/_content/tour/per/generics/multi-type-params/example1.go
index 87ca2d31..5e9f13e3 100644
--- a/_content/tour/per/generics/multi-type-params/example1.go
+++ b/_content/tour/per/generics/multi-type-params/example1.go
@@ -3,7 +3,7 @@
 // All material is licensed under the Apache License Version 2.0, January 2004
 // http://www.apache.org/licenses/LICENSE-2.0
 
-// Sample program to show how to write a generic functions tha take multiple
+// Sample program to show how to write a generic functions that take multiple
 // generic parameters.
 package main
 
diff --git a/_content/tour/pol/algorithms/sorting/insertion.go b/_content/tour/pol/algorithms/sorting/insertion.go
index 665a4a75..798c6416 100644
--- a/_content/tour/pol/algorithms/sorting/insertion.go
+++ b/_content/tour/pol/algorithms/sorting/insertion.go
@@ -25,7 +25,7 @@ func insertionSort(numbers []int) {
 	// Walk through the numbers from left to right. Through
 	// each outer loop iteration we move values from right
 	// to left inside the array when they are larger than
-	// the value that preceed it.
+	// the value that precedes it.
 
 	for i := 1; i < n; i++ {
 		j := i
diff --git a/_content/tour/pol/generics/multi-type-params/example1.go b/_content/tour/pol/generics/multi-type-params/example1.go
index 87ca2d31..5e9f13e3 100644
--- a/_content/tour/pol/generics/multi-type-params/example1.go
+++ b/_content/tour/pol/generics/multi-type-params/example1.go
@@ -3,7 +3,7 @@
 // All material is licensed under the Apache License Version 2.0, January 2004
 // http://www.apache.org/licenses/LICENSE-2.0
 
-// Sample program to show how to write a generic functions tha take multiple
+// Sample program to show how to write a generic functions that take multiple
 // generic parameters.
 package main
 
diff --git a/_content/tour/por/algorithms/sorting/insertion.go b/_content/tour/por/algorithms/sorting/insertion.go
index 665a4a75..798c6416 100644
--- a/_content/tour/por/algorithms/sorting/insertion.go
+++ b/_content/tour/por/algorithms/sorting/insertion.go
@@ -25,7 +25,7 @@ func insertionSort(numbers []int) {
 	// Walk through the numbers from left to right. Through
 	// each outer loop iteration we move values from right
 	// to left inside the array when they are larger than
-	// the value that preceed it.
+	// the value that precedes it.
 
 	for i := 1; i < n; i++ {
 		j := i
diff --git a/_content/tour/por/generics/multi-type-params/example1.go b/_content/tour/por/generics/multi-type-params/example1.go
index 87ca2d31..5e9f13e3 100644
--- a/_content/tour/por/generics/multi-type-params/example1.go
+++ b/_content/tour/por/generics/multi-type-params/example1.go
@@ -3,7 +3,7 @@
 // All material is licensed under the Apache License Version 2.0, January 2004
 // http://www.apache.org/licenses/LICENSE-2.0
 
-// Sample program to show how to write a generic functions tha take multiple
+// Sample program to show how to write a generic functions that take multiple
 // generic parameters.
 package main
 
diff --git a/_content/tour/rus/algorithms/sorting/insertion.go b/_content/tour/rus/algorithms/sorting/insertion.go
index 665a4a75..798c6416 100644
--- a/_content/tour/rus/algorithms/sorting/insertion.go
+++ b/_content/tour/rus/algorithms/sorting/insertion.go
@@ -25,7 +25,7 @@ func insertionSort(numbers []int) {
 	// Walk through the numbers from left to right. Through
 	// each outer loop iteration we move values from right
 	// to left inside the array when they are larger than
-	// the value that preceed it.
+	// the value that precedes it.
 
 	for i := 1; i < n; i++ {
 		j := i
diff --git a/_content/tour/rus/generics/multi-type-params/example1.go b/_content/tour/rus/generics/multi-type-params/example1.go
index 87ca2d31..5e9f13e3 100644
--- a/_content/tour/rus/generics/multi-type-params/example1.go
+++ b/_content/tour/rus/generics/multi-type-params/example1.go
@@ -3,7 +3,7 @@
 // All material is licensed under the Apache License Version 2.0, January 2004
 // http://www.apache.org/licenses/LICENSE-2.0
 
-// Sample program to show how to write a generic functions tha take multiple
+// Sample program to show how to write a generic functions that take multiple
 // generic parameters.
 package main
 
diff --git a/_content/tour/rus/variables.article b/_content/tour/rus/variables.article
index 1bb918a8..d8dc03bf 100644
--- a/_content/tour/rus/variables.article
+++ b/_content/tour/rus/variables.article
@@ -27,7 +27,7 @@
 - uint8 представляет беззнаковое целое число размером 1 байт
 - int32 представляет знаковое целое число размером 4 байта
 
-Когда вы объявляете тип данных без указания точности (unit, int), размер выделяемой памяти
+Когда вы объявляете тип данных без указания точности (uint, int), размер выделяемой памяти
 зависит от архитектуры компьютера на котором происходит сборка программы:
 
 - 32-битная архитектура: int представляет знаковое целое число с выделением 4 байтов памяти
diff --git a/_content/tour/tur/algorithms/sorting/insertion.go b/_content/tour/tur/algorithms/sorting/insertion.go
index 665a4a75..798c6416 100644
--- a/_content/tour/tur/algorithms/sorting/insertion.go
+++ b/_content/tour/tur/algorithms/sorting/insertion.go
@@ -25,7 +25,7 @@ func insertionSort(numbers []int) {
 	// Walk through the numbers from left to right. Through
 	// each outer loop iteration we move values from right
 	// to left inside the array when they are larger than
-	// the value that preceed it.
+	// the value that precedes it.
 
 	for i := 1; i < n; i++ {
 		j := i
diff --git a/_content/tour/tur/generics/multi-type-params/example1.go b/_content/tour/tur/generics/multi-type-params/example1.go
index 87ca2d31..5e9f13e3 100644
--- a/_content/tour/tur/generics/multi-type-params/example1.go
+++ b/_content/tour/tur/generics/multi-type-params/example1.go
@@ -3,7 +3,7 @@
 // All material is licensed under the Apache License Version 2.0, January 2004
 // http://www.apache.org/licenses/LICENSE-2.0
 
-// Sample program to show how to write a generic functions tha take multiple
+// Sample program to show how to write a generic functions that take multiple
 // generic parameters.
 package main
 
diff --git a/internal/webtest/webtest.go b/internal/webtest/webtest.go
index 950f9b62..ab9885d6 100644
--- a/internal/webtest/webtest.go
+++ b/internal/webtest/webtest.go
@@ -164,7 +164,7 @@ import (
 )
 
 // HandlerWithCheck returns an http.Handler that responds to each request
-// by running the test script files mached by glob against the handler h.
+// by running the test script files matched by glob against the handler h.
 // If the tests pass, the returned http.Handler responds with status code 200.
 // If they fail, it prints the details and responds with status code 503
 // (service unavailable).