How is Twitter different from Facebook?

Many people who have used Facebook but not Twitter may wonder how the two social networks differ. Below are some of the major differences and the strengths and weaknesses of each service.
Friends and followers
On Facebook, you're more likely to friend family and people you know. On Twitter, you can follow anyone or anything that's not private. This subtle difference makes it more likely that you'll follow your favorite sports team, celebrity, influencer, business, and other things that interest you on Twitter.
A Facebook friend request requires that both people agree to be connected. However, it's also possible to follow people on Facebook and join Facebook groups.
Visible to all, or only friends
To help with privacy concerns, when you create a Facebook account, it's only visible to friends and family. However, when you create a Twitter account, it's viewable by everyone (unless you set it to be private). This setting means you can view almost everyone's Twitter account and history even if you're not following them.
Your Facebook account privacy settings can be adjusted to be visible to everyone, friends of friends, and friends only.
Post length
Twitter is a microblogging service that only allows 280 characters per post (tweet), but Facebook allows for messages of almost any length. Because of this limitation, you'll mostly only see small posts on Twitter. Many users enjoy the smaller posts because it forces everyone to be as brief as possible. In contrast, others find it limiting when having to create multiple posts to publish something longer than 280 characters.
Hashtags

Twitter introduced the use of hashtags in tweets, allowing users to create linked topics or keywords in their posts. These topics allow other users to help sort and find posts that most interest them. Based on how many people use or view a hashtag, Twitter highlights them as trending topics.
Facebook now also supports hashtags, but they're not used as frequently as on Twitter.
Share, retweet, and favorite
When stumbling across something interesting, you can share it with your friends on Facebook. When you do, it's made available to all of your friends and followers. On Twitter, most users tweet or retweet something they find interesting to add it to their timeline. However, another popular option on Twitter is to favorite a tweet, which saves the post to your separate favorites section.
Notifications
Twitter was initially designed to be used on phones and continues to be very popular with smartphone users. Today, Twitter and Facebook can be used on smartphones, tablets, and computers.
However, with Twitter, you're given more options to customize notifications. This feature is great for keeping up-to-date with people and groups whose tweets you don't want to miss.
Options and features
When compared with Twitter, Facebook has more options of things to do, such as games you can play with friends, and Facebook Marketplace, where you can shop for items. These additional features provide users with more things to do on Facebook, but the many options may be overwhelming for some users.
Number of users
Facebook has over one billion users, and Twitter has over 200 million. With more than 800 million more followers on Facebook, it's more likely that you'll find more of your friends, family, co-workers, and customers on Facebook.
Which one should I use?
In general, Facebook is best for staying connected with people and groups who publish updates for a private group of friends, family, or community members. Twitter is best for getting updates from individuals and public figures who share things for the whole world to see.
In the end, Facebook and Twitter each have their unique features, and both help you stay connected to the people and groups you like.