Facebook has 5 core values:

Be Bold

Building great things means taking risks. We have a saying: "The riskiest thing is to take no risks." in a world that's changing so quickly you're guaranteed to fail if you don't take any risks.

Focus on Impact

To make the most impact, we need to solve the most important problems. We expect Facebook employees to avoid wasting time on minor issues and focus on truly big challenges.

Move Fast

We believe that it’s better to move fast and make mistakes than to move slowly and miss opportunities. Doing so enables us to build more things and learn faster.

Be Open

Informed people make better decisions and make a greater impact — so we work hard to ensure that everyone at Facebook can access as much information about the company as possible.

Build Social Value

At Facebook, we’re trying to bring the world closer together — not just grow our business. Our people focus on creating real value for the world — every day and in everything they do.

Engineering levels at Facebook:

• E3 (SWE II) 
• E4 (SWE III)
• E5 (Senior SWE)
• E6 (Staff SWE) 
• E7 (Senior Staff SWE)
• E8 (Principal Engineer)
• E9 (Distinguished Engineer)

Management levels at Facebook:

• M1 (Manager)
• M2 (Senior Manager)
• D1 (Director)
• D2 (Senior Director )

• Facebook app - The main web application.
• Messenger - Mobile apps to send messages to users.
• Instagram -  Photo and video-sharing social networking service.
• WhatsApp - Cross-platform messaging and Voice over IP service 
• Oculus -  Virtual reality hardware and software products.
• Workplace - An online team collaboration tool using Facebook features for work.
• Portal - Connect family and friends, voice, video, Alexa, etc.
• Calibra - The Calibra wallet app is built on blockchain technology to enable people to move Libra (cryptocurrency).

The top 10 Facebook competitors are Google, Apple, Amazon, YouTube, Twitter, Microsoft, Snap, WeChat, LinkedIn and Pinterest.

• Google competes with Facebook in advertising.  The ad market share of Google is about 41% whereas Facebook has about 16% market share.
• Snapchat is a big competitor for Facebook's Messenger and Instagram.
• Pinterest competes with Facebook over referral traffic to business websites.
• Facebook competes with Amazon over ad share and streaming services like Twitch.
• Youtube competes with Facebook for videos and live streaming with over 2 billion active users.
• LinkedIn with a huge user base competes with Facebook among the professional crowd.

• Paid leave for new parents
• Free Lunch
• Free Snacks
• A 30-day paid break every five years.
• Wellness Reimbursement
• Housing Stipend 
• Competitive retirement plan
• On-Site Gym
• Transportation
• Health Benefits
• Company Phones

• Given two strings S and T, determine if they are both one edit distance apart.
• Given an array nums and a target value k, find the maximum length of a subarray that sums to k.
• Given a binary search tree and a node in it, find the in-order successor of that node in the BST.
• Sort out the top K frequently used words by users.
• Given an array of meeting time intervals consisting of start and end times, find the minimum number of conference rooms required.
• Given a string, find the length of the longest substring T that contains at most k distinct characters.
• Given a stream of integers and a window size, calculate the moving average of all integers in the sliding window.
• Given a string, determine if a permutation of the string could form a palindrome.
• Given a binary tree, find the length of the longest consecutive sequence path.
• Given a binary tree, return the vertical order traversal of its nodes' values. (ie, from top to bottom, column by column).
• Reverse a doubly linked list.
• Given a string s of '(' , ')' and lowercase English characters. Your task is to remove the minimum number of parentheses ( '(' or ')', in any positions ) so that the resulting parentheses string is valid and return any valid string.
• Given a non-empty string s, you may delete at most one character. Judge whether you can make it a palindrome.
• Construct a binary tree from preorder and inorder traversal.
• Given an array nums, write a function to move all 0's to the end of it while maintaining the relative order of the non-zero elements.
• Given n non-negative integers representing an elevation map where the width of each bar is 1, compute how much water it is able to trap after raining.

• Design Instagram.
• Design a web Crawler.
• Design and Location-Based Android application to track the user whereabouts.
• Design a recommendation system for products.
• Design a web crawler. Design Dropbox.
• Design an instant messenger platform.
• Design a URL shortener. Design Facebook NewsFeed feature. Design Twitter.

• What were some of the best things you've built?
• What could you have done better?
• Why Facebook?
• What were some excellent collaborations you've had?
• Tell me about a time when you advocated for and pushed your own ideas forward despite opposition?
• How do you deal with conflict?
• How do you like to give and receive feedback?
• What kinds of technologies are you most excited about?
• Tell me about time you took a risk and you failed?
• Tell me about a time you had an innovative idea that had a positive impact.
• How did you handle a task where you had a deadline that you couldn’t meet?
• Tell me time when you have to make a pivot and choose a different approach or solution.
• Share an example of how you were able to motivate employees or co-workers.