to keep your messages private.

以保持你的資訊的私密性。

It's available on both mobile and desktop,

它在移動和桌面上都可以使用。

but for this video,

但對於這個視頻。

we'll be focusing on the mobile app.

我們將專注於移動應用程序。

With Signal, the only people who can see

有了Signal，唯一能看到的人是

the messages you send

您發送的資訊

are you and the person who receives them,

是你和接受他們的人。

because they're encrypted.

因為它們是加密的。

However, Signal's messages are only secure

然而，Signal的資訊只是安全的

if both the sender and receiver are on the app.

如果發送方和接收方都在該應用程序上。

You can download Signal for iPhone or Android for free.

你可以免費下載iPhone或Android的Signal。

We'll be using an iPhone for this tutorial.

我們將在本教程中使用iPhone。

First, go to the Apple store and search for Signal.

首先，去蘋果商店，搜索Signal。

Once you find it, tap on "GET" or "Download."

一旦你找到它，點擊 "獲取 "或 "下載"。

Once you've downloaded it,

一旦你下載了它。

you can sign up with your cellphone number.

你可以用你的手機號碼進行註冊。

The app can automatically detect

該應用程序可以自動檢測

which of your contacts also use Signal,

你的哪些聯繫人也使用Signal。

and you can always click on "Invite Friends to Signal"

而且你可以隨時點擊 "邀請朋友加入信號"。

to choose more people.

以選擇更多的人。

Chats look nearly identical to iMessage,

聊天記錄看起來與iMessage幾乎相同。

with similar features, like sending texts and photos.

具有類似的功能，如發送簡訊和照片。

You can also make secure voice calls over a data network.

你還可以通過數據網絡進行安全的語音通話。

Each person is shown a random pair of words

每個人都會看到一對隨機的單詞

that they can use to verify the call is secure.

他們可以用來驗證呼叫是否安全。

In this case, you tell the person that you're calling

在這種情況下，你告訴對方你要打電話給他

"chisel" and they'd reply "sociable" for verification.

"鑿子"，他們會回答 "善於交際"，以便核實。