Chat

What is Chat?

Chat in video conferencing is a text-based messaging feature that allows participants to send written messages to each other during a meeting. Chat provides a parallel communication channel alongside audio and video, enabling participants to share links, ask questions, provide feedback, or have side conversations without interrupting the main discussion.

Modern chat implementations offer public messages (visible to all), private messages (direct messages to specific participants), file sharing, emoji reactions, and formatting options, making chat an essential complement to verbal communication in virtual meetings.

Types of Chat Messages

Public Chat (To Everyone)

Messages visible to all meeting participants:

Use Cases: Share links, resources, questions for all to see
Visibility: All participants can see and respond
Persistent: Messages remain visible throughout meeting
Archived: Often saved with meeting transcript/recording

// Send public chat message
const publicMessage = {
  id: generateId(),
  type: 'public',
  senderId: currentUserId,
  senderName: 'John Doe',
  content: 'Here is the link: https://example.com/document',
  timestamp: Date.now(),
  edited: false
};

broadcastToMeeting(meetingId, {
  type: 'chat-message',
  message: publicMessage
});

Private Messages (Direct Messages)

One-on-one messages between two participants:

Use Cases: Sidebar conversations, private questions, technical assistance
Visibility: Only sender and recipient can see
Privacy: Host may or may not be able to see private chats (platform dependent)
Discretion: Allows conversations without distracting entire meeting

// Send private message
const privateMessage = {
  id: generateId(),
  type: 'private',
  senderId: currentUserId,
  recipientId: targetUserId,
  content: 'Can you share that resource after the meeting?',
  timestamp: Date.now()
};

// Send only to recipient
sendToParticipant(targetUserId, {
  type: 'chat-message',
  message: privateMessage
});

Host-Only Messages

Messages sent to hosts/moderators only:

Use Cases: Technical issues, questions, requests for help
Visibility: Only hosts and co-hosts receive
Support: Allows participants to get help without disrupting meeting

Chat Features and Capabilities

Rich Text Formatting

Modern chat supports various formatting options:

Bold/Italic/Strikethrough: **bold**, *italic*, ~~strikethrough~~
Code Blocks: Monospaced text for code snippets
Links: Auto-detect and linkify URLs
Mentions: @username to notify specific participants
Emojis: 😊 👍 🎉 for quick reactions

File Sharing

Share files through chat interface:

Document Sharing: PDFs, Word docs, spreadsheets
Images: Screenshots, diagrams, photos
Size Limits: Typically 10-200 MB depending on platform
Security Scanning: Automatic virus/malware scanning
Expiration: Files may expire after meeting ends or specific period

// Send file via chat
async function sendFile(file) {
  // Upload file to server
  const uploadedFile = await uploadFile(file);
  
  const fileMessage = {
    id: generateId(),
    type: 'public',
    senderId: currentUserId,
    contentType: 'file',
    file: {
      name: file.name,
      size: file.size,
      type: file.type,
      url: uploadedFile.url
    },
    timestamp: Date.now()
  };
  
  broadcastToMeeting(meetingId, {
    type: 'chat-message',
    message: fileMessage
  });
}

Reactions and Emojis

Quick Reactions: One-click emoji responses
Message Reactions: React to specific messages (like Slack)
Emoji Picker: Browse and select from emoji library
Skin Tones: Support for diverse emoji variations

Message Management

Edit Messages: Modify sent messages (with "edited" indicator)
Delete Messages: Remove messages (may leave "deleted" placeholder)
Reply Threading: Reply to specific messages creating threads
Search: Search chat history for keywords
Pin Messages: Highlight important messages at top of chat

Host Controls

Moderation Capabilities

Hosts can manage chat activity:

Disable Chat: Turn off chat entirely
Restrict Recipients: Allow messages only to host, or everyone
Delete Messages: Remove inappropriate or spam messages
Mute Participants: Prevent specific users from chatting
Save Chat: Export chat transcript for archival

// Host control: Restrict chat to host-only
function restrictChatToHost(meetingId) {
  const meeting = meetings.get(meetingId);
  
  meeting.settings.chatPolicy = 'host-only';
  
  // Notify all participants
  broadcastToMeeting(meetingId, {
    type: 'chat-policy-changed',
    policy: 'host-only',
    message: 'Chat is now restricted. You can only send messages to the host.'
  });
}

Chat Policies

Common chat permission configurations:

Everyone Can Chat: All participants can message anyone
Public Only: Disable private messages, allow public chat
Host Only: Participants can only message host/co-hosts
No Chat: Disable chat completely
No Private Chat: Allow public, disable direct messages

Implementation with WebSockets

Real-Time Chat Infrastructure

// Server-side: Handle chat messages
socket.on('send-chat-message', ({ meetingId, message }) => {
  const participant = getParticipant(socket.userId, meetingId);
  
  // Validate permissions
  if (!canSendChat(participant, message.type)) {
    return socket.emit('error', { message: 'Chat permission denied' });
  }
  
  // Add server metadata
  message.id = generateId();
  message.timestamp = Date.now();
  message.senderName = participant.name;
  
  // Store message
  saveChatMessage(meetingId, message);
  
  // Broadcast based on message type
  if (message.type === 'public') {
    // Send to all participants
    broadcastToMeeting(meetingId, {
      type: 'chat-message',
      message: message
    });
  } else if (message.type === 'private') {
    // Send to recipient only
    sendToParticipant(message.recipientId, {
      type: 'chat-message',
      message: message
    });
    // Echo back to sender
    socket.emit('chat-message', { message });
  }
});

Client-Side Chat UI

// Client: Send chat message
function sendChatMessage(content, type = 'public', recipientId = null) {
  const message = {
    type: type,
    content: content,
    recipientId: recipientId
  };
  
  socket.emit('send-chat-message', {
    meetingId: currentMeetingId,
    message: message
  });
}

// Receive and display messages
socket.on('chat-message', ({ message }) => {
  displayChatMessage(message);
  
  // Show notification if chat panel is closed
  if (!isChatPanelVisible()) {
    showChatNotification(message);
    incrementUnreadCount();
  }
  
  // Play notification sound
  if (message.senderId !== currentUserId) {
    playNotificationSound();
  }
});

Common Use Cases

Q&A Sessions: Participants submit questions via chat, host/moderator answers verbally
Link Sharing: Share resources, documents, or references without interrupting speaker
Multilingual Support: Provide translations or explanations in chat
Technical Support: IT staff provide help via private chat during meetings
Feedback Collection: Gather quick feedback or poll responses
Accessibility: Supplement audio for hearing-impaired participants
Meeting Notes: Collaborative note-taking in chat
Engagement: Increase participation from quieter attendees

Best Practices

For Participants

Stay On Topic: Keep chat relevant to meeting discussion
Use @Mentions: Direct questions to specific people
Avoid Spam: Don't flood chat with excessive messages
Check Audience: Verify you're sending to correct recipient (public vs private)
Professional Tone: Maintain same professionalism as in verbal communication

For Hosts

Monitor Chat: Assign co-host to watch chat during presentations
Acknowledge Messages: Periodically address questions from chat
Set Expectations: Explain chat policy at meeting start
Save Transcript: Export chat for follow-up on questions/action items
Moderate Actively: Address inappropriate messages quickly

Meeting Etiquette

Introduce Yourself: Start with name if chatting for first time
Use Sparingly During Presentations: Avoid distracting speaker
Proofread: Check for typos before sending, especially in professional settings
Respect Privacy: Don't screenshot or share private messages

Advanced Features (2025)

AI-Powered Capabilities

Auto-Translation: Real-time translation of chat messages
Smart Suggestions: Suggested responses based on context
Sentiment Analysis: Detect confusion, questions, or negative sentiment
Auto-Summarization: AI generates summary of chat discussion
Topic Detection: Automatically categorize and group messages by topic

Integration Features

Slash Commands: /poll, /remind, /schedule for quick actions
Bot Integration: Chatbots for information, support, or automation
External App Links: Deep links to Jira, Trello, Google Docs
GIF Support: Animated GIF reactions and responses

Security and Privacy

Encryption

In-Transit Encryption: TLS/SSL for message transmission
End-to-End Encryption: Some platforms offer E2EE for chat (less common)
At-Rest Encryption: Encrypted storage of chat archives

Data Retention

Meeting Duration Only: Chat deleted when meeting ends
Short-Term Retention: Available for 24-48 hours post-meeting
Long-Term Archive: Saved indefinitely for compliance
User Export: Participants can save their own copy

Compliance

GDPR: Right to deletion, data portability
eDiscovery: Legal hold and search capabilities
Audit Logs: Track who sent what and when
DLP Integration: Scan for sensitive data (SSN, credit cards)

Accessibility

Screen Reader Support: Announce new messages to visually impaired users
Keyboard Shortcuts: Ctrl+K to focus chat, arrow keys to navigate
High Contrast: Support for high contrast themes
Font Scaling: Respect system font size settings
Alternative to Audio: Critical for deaf/hard-of-hearing participants

Platform Examples

Zoom: Public/private chat, file sharing, save transcript, restrict chat permissions
Microsoft Teams: Threaded conversations, rich formatting, GIFs, @mentions, deep integration with Teams chat
Google Meet: Simple chat interface, chat saved to meeting organizer's Drive
Slack Huddles: Integrated with Slack channels, persistent chat beyond meeting
Discord: Voice channels with persistent text chat, rich embed support

Performance Considerations

Message Throttling: Limit messages per user per minute to prevent spam
History Limits: Only load recent N messages, lazy-load older history
File Size Limits: Prevent large file uploads that slow down experience
Typing Indicators: Show who is typing (with debouncing to reduce traffic)