A variable name<\/strong> is the name of the box<\/strong> where we store data.<\/p>\n Example:<\/p>\n Here:<\/p>\n Good variable names make your code: Bad names make code confusing \ud83d\ude15<\/p>\n Python has some simple rules. \u2714 Allowed:<\/p>\n \u274c Not Allowed:<\/p>\n \u2714 Allowed:<\/p>\n \u274c Not Allowed:<\/p>\n You cannot use Python reserved words.<\/p>\n \u274c Wrong:<\/p>\n \u2714 Correct:<\/p>\n These are two different variables<\/strong>.<\/p>\n Python uses snake_case<\/strong>.<\/p>\n (These work, but are hard to understand.)<\/p>\n Meaningful names are better.<\/p>\n \u2714 Correct:<\/p>\n \u2714 Correct:<\/p>\n \u274c Wrong:<\/p>\n \u2714 Correct:<\/p>\n \u2714 Variable name is the name of the data box This chapter is ideal for:<\/p>\n Python beginner books<\/p>\n<\/li>\n School students<\/p>\n<\/li>\n Self-learners<\/p>\n<\/li>\n<\/ul>\n If you want next, I can write:<\/p>\n Python Data Types<\/strong><\/p>\n<\/li>\n Python Operators<\/strong><\/p>\n<\/li>\n if\u2013else statements<\/strong><\/p>\n<\/li>\n Loops (for, while)<\/strong><\/p>\n<\/li>\n Practice questions with answers<\/strong><\/p>\n<\/li>\n<\/ul>\n Just tell me \ud83d\ude0a<\/p>\n","protected":false},"excerpt":{"rendered":" 1. What is a Variable Name? A variable name is the name of the box where we store data. Example: age = 25 Here: age is the variable name 25 is the value 2....<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[21],"tags":[],"class_list":["post-2381","post","type-post","status-publish","format-standard","hentry","category-python"],"_links":{"self":[{"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts\/2381","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/comments?post=2381"}],"version-history":[{"count":1,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts\/2381\/revisions"}],"predecessor-version":[{"id":2382,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/posts\/2381\/revisions\/2382"}],"wp:attachment":[{"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/media?parent=2381"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/categories?post=2381"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/demo.materiamedica.net\/demo6\/wp-json\/wp\/v2\/tags?post=2381"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}age = 25<\/span>
\n<\/code><\/div>\n<\/div>\n\n
age<\/code> is the variable name<\/strong><\/p>\n<\/li>\n25<\/code> is the value<\/p>\n<\/li>\n<\/ul>\n2. Why Variable Names Are Important<\/h2>\n
\n\u2714 Easy to read
\u2714 Easy to understand
\u2714 Easy to fix later<\/p>\n3. Rules for Variable Names in Python<\/h2>\n
You must follow these rules<\/strong>, or Python will give an error.<\/p>\n\u2705 Rule 1: Start with a Letter or
_<\/code><\/h3>\nname = \"Amit\"<\/span>
\n_age = 20<\/span>
\n<\/code><\/div>\n<\/div>\n1name = \"Error\"<\/span>
\n<\/code><\/div>\n<\/div>\n\u2705 Rule 2: Use Only Letters, Numbers, and
_<\/code><\/h3>\nstudent_name = \"Ravi\"<\/span>
\nmarks1 = 80<\/span>
\n<\/code><\/div>\n<\/div>\ntotal-marks = 90<\/span>
\nmy name = \"Rahul\"<\/span>
\n<\/code><\/div>\n<\/div>\n\u2705 Rule 3: No Python Keywords<\/h3>\n
class<\/span> = 10<\/span>
\nif<\/span> = 5<\/span>
\n<\/code><\/div>\n<\/div>\nclass_name = \"Ten\"<\/span>
\nif_value = 5<\/span>
\n<\/code><\/div>\n<\/div>\n\u2705 Rule 4: Variable Names Are Case-Sensitive<\/h3>\n
name = \"Amit\"<\/span>
\nName = \"Ravi\"<\/span>
\n<\/code><\/div>\n<\/div>\n4. Good Variable Naming Style (Best Practice)<\/h2>\n
Good Names \ud83d\udc4d<\/h3>\n
student_name = \"Anita\"<\/span>
\ntotal_marks = 450<\/span>
\nuser_age = 21<\/span>
\n<\/code><\/div>\n<\/div>\nBad Names \ud83d\udc4e<\/h3>\n
x = 10<\/span>
\ntm = 450<\/span>
\na1 = 21<\/span>
\n<\/code><\/div>\n<\/div>\n5. Short vs Meaningful Names<\/h2>\n
Bad Example<\/h3>\n
x = 500<\/span>
\n<\/code><\/div>\n<\/div>\nGood Example<\/h3>\n
total_price = 500<\/span>
\n<\/code><\/div>\n<\/div>\n6. Multiple Variable Names<\/h2>\n
Example<\/h3>\n
first_name = \"Rahul\"<\/span>
\nlast_name = \"Sharma\"<\/span>
\n<\/code><\/div>\n<\/div>\n7. Common Beginner Mistakes<\/h2>\n
\u274c Using Spaces<\/h3>\n
my name = \"Ravi\"<\/span>
\n<\/code><\/div>\n<\/div>\nmy_name = \"Ravi\"<\/span>
\n<\/code><\/div>\n<\/div>\n\u274c Starting with Number<\/h3>\n
2age = 20<\/span>
\n<\/code><\/div>\n<\/div>\nage2 = 20<\/span>
\n<\/code><\/div>\n<\/div>\n8. Practice Examples<\/h2>\n
Example 1: Correct Names<\/h3>\n
book_title = \"Python Basics\"<\/span>
\npage_count = 120<\/span>
\nprice = 299<\/span>
\n<\/code><\/div>\n<\/div>\nExample 2: Fix the Wrong Names<\/h3>\n
1price = 100<\/span>
\ntotal-price = 500<\/span>
\n<\/code><\/div>\n<\/div>\nprice1 = 100<\/span>
\ntotal_price = 500<\/span>
\n<\/code><\/div>\n<\/div>\n9. Summary (Variable Names)<\/h2>\n
\u2714 Must start with letter or _<\/code>
\u2714 No spaces or special symbols
\u2714 No Python keywords
\u2714 Use meaningful names<\/p>\n\ud83d\udcd8 Perfect for Beginner eBook<\/h3>\n
\n
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