diff --git a/readMe.md b/readMe.md index d3ab83bf..813e0b4d 100644 --- a/readMe.md +++ b/readMe.md @@ -180,15 +180,15 @@ We add comments to our code. Comments are very important to make code more reada Example: Single Line Comment - // This is the first comment - // This is the second comment - // I am a single line comment + // This is the first comment + // This is the second comment + // I am a single line comment Example: Multiline Comment /* - This is a multiline comment - Multiline comments can take multiple lines - JavaScript is the language of the web + This is a multiline comment + Multiline comments can take multiple lines + JavaScript is the language of the web */ ##### Syntax @@ -450,11 +450,12 @@ Variables are _containers_ of data. Variables used to _store_ data in a memory l For a variable that changes at a different time, we use _let_. If the data does not change at all, we use _const_. For example, PI, country name, gravity do no change, and we can use *const*. -A JavaScript variable name should not begin with a number. -A JavaScript variable name does not allow special characters except dollar sign and underscore. -A JavaScript variable name follows a camelCase convention. -A JavaScript variable name should not have space between words. The following are valid examples of JavaScript variables. +* A JavaScript variable name should not begin with a number. +* A JavaScript variable name does not allow special characters except dollar sign and underscore. +* A JavaScript variable name follows a camelCase convention. +* A JavaScript variable name should not have space between words. +The following are valid examples of JavaScript variables. Valid variables in JavaScript: ```js firstName @@ -477,15 +478,14 @@ Valid variables in JavaScript: year2020 year_2020 ``` -Camel case or the first way of declaring is conventional in JavaScript. In this material, camelCase variables will be used. - +camelCase or the first way of declaring is conventional in JavaScript. In this material, we will use camelCase variables. Invalid variable: ```sh first-name 1_num num_#_1 ``` -Let's declare variables with different data types. To declare a variable, we need to use let or const keyword before the variable name. Following the variable name, we write an equal sign (assignment operator), and a value. +Let us declare variables with different data types. To declare a variable, we need to use let or const keyword before the variable name. Following the variable name, we write an equal sign (assignment operator), and a value. ```js # Syntax let nameOfVariable = value @@ -1152,17 +1152,17 @@ let falseValue = 3 < 4 // false ``` We agreed that boolean values are either true or false. ### Truthy values: --- All numbers(positive and negative) are truthy except zero --- All strings are truthy --- The boolean true +* All numbers(positive and negative) are truthy except zero +* All strings are truthy +* The boolean true ### Falsy values: --- 0 --- 0n --- null --- undefined --- NaN --- the boolean false --- '', "", ``, empty string +* 0 +* 0n +* null +* undefined +* NaN +* the boolean false +* '', "", ``, empty string It is good to remember those truthy values and falsy values. In later section, we will use them with conditions to make decision. ## Undefined @@ -1494,6 +1494,12 @@ let firstName = 'Asabeneh' let lastName = 'Yetayeh Your first name, Asabeneh is longer than your family name, Yetayeh ``` +3. Declare two variables _myAge_ and _yourAge_ and assign them initial values and myAge and yourAge. + Output: + ```sh + let myAge = 250 + let yourAge = 25 + I am 225 years older than you. ## 7. Exercises: Date time Object 1. What is the year today?