diff --git a/includes/api/class-wc-rest-coupons-controller.php b/includes/api/class-wc-rest-coupons-controller.php
index 55c35ce8188..1864cebcdff 100644
--- a/includes/api/class-wc-rest-coupons-controller.php
+++ b/includes/api/class-wc-rest-coupons-controller.php
@@ -339,7 +339,7 @@ class WC_REST_Coupons_Controller extends WC_REST_Legacy_Coupons_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'amount' => array(
-					'description' => __( 'The amount of discount.', 'woocommerce' ),
+					'description' => __( 'The amount of discount. Should always be numeric, even if setting a percentage.', 'woocommerce' ),
 					'type'        => 'string',
 					'context'     => array( 'view', 'edit' ),
 				),
@@ -396,13 +396,13 @@ class WC_REST_Coupons_Controller extends WC_REST_Legacy_Coupons_Controller {
 					'readonly'    => true,
 				),
 				'individual_use' => array(
-					'description' => __( 'Whether coupon can only be used individually.', 'woocommerce' ),
+					'description' => __( 'If true, the coupon can only be used individually. Other applied coupons will be removed from the cart.', 'woocommerce' ),
 					'type'        => 'boolean',
 					'default'     => false,
 					'context'     => array( 'view', 'edit' ),
 				),
 				'product_ids' => array(
-					'description' => __( "List of product ID's the coupon can be used on.", 'woocommerce' ),
+					'description' => __( "List of product IDs the coupon can be used on.", 'woocommerce' ),
 					'type'        => 'array',
 					'items'       => array(
 						'type'    => 'integer',
@@ -410,7 +410,7 @@ class WC_REST_Coupons_Controller extends WC_REST_Legacy_Coupons_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'excluded_product_ids' => array(
-					'description' => __( "List of product ID's the coupon cannot be used on.", 'woocommerce' ),
+					'description' => __( "List of product IDs the coupon cannot be used on.", 'woocommerce' ),
 					'type'        => 'array',
 					'items'       => array(
 						'type'    => 'integer',
@@ -418,7 +418,7 @@ class WC_REST_Coupons_Controller extends WC_REST_Legacy_Coupons_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'usage_limit' => array(
-					'description' => __( 'How many times the coupon can be used.', 'woocommerce' ),
+					'description' => __( 'How many times the coupon can be used in total.', 'woocommerce' ),
 					'type'        => 'integer',
 					'context'     => array( 'view', 'edit' ),
 				),
@@ -433,13 +433,13 @@ class WC_REST_Coupons_Controller extends WC_REST_Legacy_Coupons_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'free_shipping' => array(
-					'description' => __( 'Define if can be applied for free shipping.', 'woocommerce' ),
+					'description' => __( 'If true and if the free shipping method requires a coupon, this coupon will enable free shipping.', 'woocommerce' ),
 					'type'        => 'boolean',
 					'default'     => false,
 					'context'     => array( 'view', 'edit' ),
 				),
 				'product_categories' => array(
-					'description' => __( "List of category ID's the coupon applies to.", 'woocommerce' ),
+					'description' => __( "List of category IDs the coupon applies to.", 'woocommerce' ),
 					'type'        => 'array',
 					'items'       => array(
 						'type'    => 'integer',
@@ -447,7 +447,7 @@ class WC_REST_Coupons_Controller extends WC_REST_Legacy_Coupons_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'excluded_product_categories' => array(
-					'description' => __( "List of category ID's the coupon does not apply to.", 'woocommerce' ),
+					'description' => __( "List of category IDs the coupon does not apply to.", 'woocommerce' ),
 					'type'        => 'array',
 					'items'       => array(
 						'type'    => 'integer',
@@ -455,7 +455,7 @@ class WC_REST_Coupons_Controller extends WC_REST_Legacy_Coupons_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'exclude_sale_items' => array(
-					'description' => __( 'Define if should not apply when have sale items.', 'woocommerce' ),
+					'description' => __( 'If true, this coupon will not be applied to items that have sale prices.', 'woocommerce' ),
 					'type'        => 'boolean',
 					'default'     => false,
 					'context'     => array( 'view', 'edit' ),
@@ -479,7 +479,7 @@ class WC_REST_Coupons_Controller extends WC_REST_Legacy_Coupons_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'used_by' => array(
-					'description' => __( 'List of user IDs who have used the coupon.', 'woocommerce' ),
+					'description' => __( 'List of user IDs (or guest email addresses) who have used the coupon.', 'woocommerce' ),
 					'type'        => 'array',
 					'items'       => array(
 						'type'    => 'integer',
diff --git a/includes/api/v1/class-wc-rest-coupons-controller.php b/includes/api/v1/class-wc-rest-coupons-controller.php
index 717de033655..7a92b98df03 100644
--- a/includes/api/v1/class-wc-rest-coupons-controller.php
+++ b/includes/api/v1/class-wc-rest-coupons-controller.php
@@ -447,7 +447,7 @@ class WC_REST_Coupons_V1_Controller extends WC_REST_Posts_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'amount' => array(
-					'description' => __( 'The amount of discount.', 'woocommerce' ),
+					'description' => __( 'The amount of discount. Should always be numeric, even if setting a percentage.', 'woocommerce' ),
 					'type'        => 'string',
 					'context'     => array( 'view', 'edit' ),
 				),
@@ -463,13 +463,13 @@ class WC_REST_Coupons_V1_Controller extends WC_REST_Posts_Controller {
 					'readonly'    => true,
 				),
 				'individual_use' => array(
-					'description' => __( 'Whether coupon can only be used individually.', 'woocommerce' ),
+					'description' => __( 'If true, the coupon can only be used individually. Other applied coupons will be removed from the cart.', 'woocommerce' ),
 					'type'        => 'boolean',
 					'default'     => false,
 					'context'     => array( 'view', 'edit' ),
 				),
 				'product_ids' => array(
-					'description' => __( "List of product ID's the coupon can be used on.", 'woocommerce' ),
+					'description' => __( "List of product IDs the coupon can be used on.", 'woocommerce' ),
 					'type'        => 'array',
 					'items'       => array(
 						'type'    => 'integer',
@@ -477,7 +477,7 @@ class WC_REST_Coupons_V1_Controller extends WC_REST_Posts_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'exclude_product_ids' => array(
-					'description' => __( "List of product ID's the coupon cannot be used on.", 'woocommerce' ),
+					'description' => __( "List of product IDs the coupon cannot be used on.", 'woocommerce' ),
 					'type'        => 'array',
 					'items'       => array(
 						'type'    => 'integer',
@@ -485,7 +485,7 @@ class WC_REST_Coupons_V1_Controller extends WC_REST_Posts_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'usage_limit' => array(
-					'description' => __( 'How many times the coupon can be used.', 'woocommerce' ),
+					'description' => __( 'How many times the coupon can be used in total.', 'woocommerce' ),
 					'type'        => 'integer',
 					'context'     => array( 'view', 'edit' ),
 				),
@@ -500,13 +500,13 @@ class WC_REST_Coupons_V1_Controller extends WC_REST_Posts_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'free_shipping' => array(
-					'description' => __( 'Define if can be applied for free shipping.', 'woocommerce' ),
+					'description' => __( 'If true and if the free shipping method requires a coupon, this coupon will enable free shipping.', 'woocommerce' ),
 					'type'        => 'boolean',
 					'default'     => false,
 					'context'     => array( 'view', 'edit' ),
 				),
 				'product_categories' => array(
-					'description' => __( "List of category ID's the coupon applies to.", 'woocommerce' ),
+					'description' => __( "List of category IDs the coupon applies to.", 'woocommerce' ),
 					'type'        => 'array',
 					'items'       => array(
 						'type'    => 'integer',
@@ -514,7 +514,7 @@ class WC_REST_Coupons_V1_Controller extends WC_REST_Posts_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'excluded_product_categories' => array(
-					'description' => __( "List of category ID's the coupon does not apply to.", 'woocommerce' ),
+					'description' => __( "List of category IDs the coupon does not apply to.", 'woocommerce' ),
 					'type'        => 'array',
 					'items'       => array(
 						'type'    => 'integer',
@@ -522,7 +522,7 @@ class WC_REST_Coupons_V1_Controller extends WC_REST_Posts_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'exclude_sale_items' => array(
-					'description' => __( 'Define if should not apply when have sale items.', 'woocommerce' ),
+					'description' => __( 'If true, this coupon will not be applied to items that have sale prices.', 'woocommerce' ),
 					'type'        => 'boolean',
 					'default'     => false,
 					'context'     => array( 'view', 'edit' ),
@@ -546,7 +546,7 @@ class WC_REST_Coupons_V1_Controller extends WC_REST_Posts_Controller {
 					'context'     => array( 'view', 'edit' ),
 				),
 				'used_by' => array(
-					'description' => __( 'List of user IDs who have used the coupon.', 'woocommerce' ),
+					'description' => __( 'List of user IDs (or guest email addresses) who have used the coupon.', 'woocommerce' ),
 					'type'        => 'array',
 					'items'       => array(
 						'type'    => 'integer',
diff --git a/includes/class-wc-coupon.php b/includes/class-wc-coupon.php
index a761dca89c6..ef1a3abdfb6 100644
--- a/includes/class-wc-coupon.php
+++ b/includes/class-wc-coupon.php
@@ -1045,7 +1045,7 @@ class WC_Coupon extends WC_Legacy_Coupon {
 			$valid = true;
 		}
 
-		// Specific product ID's excluded from the discount
+		// Specific product IDs excluded from the discount
 		if ( sizeof( $this->get_excluded_product_ids() ) && sizeof( array_intersect( $product_ids, $this->get_excluded_product_ids() ) ) ) {
 			$valid = false;
 		}
diff --git a/includes/class-wc-install.php b/includes/class-wc-install.php
index e8e2672412c..4d16feab2e3 100644
--- a/includes/class-wc-install.php
+++ b/includes/class-wc-install.php
@@ -309,7 +309,7 @@ class WC_Install {
 	}
 
 	/**
-	 * Create pages that the plugin relies on, storing page id's in variables.
+	 * Create pages that the plugin relies on, storing page IDs in variables.
 	 */
 	public static function create_pages() {
 		include_once( dirname( __FILE__ ) . '/admin/wc-admin-functions.php' );
diff --git a/includes/class-wc-query.php b/includes/class-wc-query.php
index 6ecb4b31992..ad05e3d6c0a 100644
--- a/includes/class-wc-query.php
+++ b/includes/class-wc-query.php
@@ -744,7 +744,7 @@ class WC_Query {
 	}
 
 	/**
-	 * Get an unpaginated list all product ID's (both filtered and unfiltered). Makes use of transients.
+	 * Get an unpaginated list all product IDs (both filtered and unfiltered). Makes use of transients.
 	 * @deprecated 2.6.0 due to performance concerns
 	 */
 	public function get_products_in_view() {