This feature is available in macOS Big Sur or later. Their name is then highlighted in the message, and they will receive a notification letting them know that they have been mentioned.

To help bring your message to the attention of a recipient, include before their name, like Or click their name after you type it.

To include other items, such as Memoji stickers, GIFs, and message effects such as balloons or confetti, click the Apps button.To include an audio recording, click the Record Audio button and record your message.To include an image or other file, drag or paste it into the message field.To include emoji, click the Emoji Picker button.Press Tab or click the message field at the bottom of the window, then type your message.Then, tap the new message button at the top of your message screen, which will probably look like a plus sign or a notepad with a pen. Or click the Add button and choose from your contacts. To send a text message with a smartphone, start by finding the messaging icon on your phones home screen and tapping on it. If you haven’t set up iMessage, enter in your Apple ID info and hit Sign in. Type the name, email address, or phone number of one or more recipients. It’s a simple way to send texts, SMS messages, and even Facetime from your Mac or iPad.

Click the New Message button at the top of the Messages window.You might be asked to sign in with your Apple ID. Along with everything else these days (October 2020), the entire experience was just Bizarre. A hostile corporate overlord that I don't recall being this evil in the past but will be looking into switching services out of in the future. After three phone numbers given to call, one 20 plus minute wait for a call back followed by 20 minutes of a phone wait message designed to irritate the ears (I discovered that if you lowered the volume to the lowest possible and wrapped the phone in several layers of thick toweling, you can almost think about other things while still listening for a near human voice) followed by 10 minutes of total silence while no one came on the line, and never even getting to the fun part where a supposedly live person puts me through the useless trouble shooting (as described multiple times above) of my device (I was texted a link with more information, if I wanted to sign in and read while waiting, thus again, solving it on my own), I can only conclude the problem is with AT & T. I came here after more than an hour just trying to get the RIGHT customer support tech person on the line to discuss the problem of texts not sending to a particular friend-intermittently.

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