IRC vs Telegram

The IRC protocol is public and open, it is mature and stable, and has been implemented in numerous projects. This means that it can be used freely, for both open-source and commercial projects.

IRC offers choice. Choice in clients (mobile, desktop, web), in scripts those clients run, in servers and features those servers have. You can even set up your own server.

Compared to other common solutions, IRC can be ignored when you are occupied doing something else. Most clients don't pester you with sounds or distracting visuals.

Every notable IRC client supports mentions - notifying you when your name is mentioned in the chat. The mentions in IRC are comparably better than Discord. Mentions used in Discord are easily abused; this doesn't happen in IRC. If someone's talking about you, you get a notification in IRC. This doesn't happen in something like Discord.

IRC has been around since 1988, so there is a ton of existing software to work with it. Everything from clients, to chat bots, to bouncers is already built.

You can choose your favorite server for an IRC network.

No need to sign up for access, confirm your e-mail address. Just choose a nickname and you're done.

IRC is user friendly if you use something like hexchat or kiwi webchat.

Direct Client-to-Client allows users to share files in a similar way to torrenting.

Twitter hashtags came from IRC channel names.

Copy/paste videos, gifs, images, geolocation, documents, and even executable files. Drag over files for practically any time up to 2GB in size. Images can be compressed, too.

The application is available free of cost.

In addition to the end-to-end encryption [only in secret chats] that provides privacy to communications, the app also includes self destructing timers for chats, and the ability to permanently delete messages, yours and theirs, from your and their devices.

Videos, gifs, images, geolocation, and documents.

Broadcasting channels suitable for announcing things.

Very customizable with a lot of clean looking options.

In Supergroups, anyone along with admins can delete their messages from all sides. A message can be pinned to the top. All of the user's messages can be deleted by an administrator, and they can be banned and reported as well. Supergroups can have a public link (outside of Asia, due to high spam volumes), which is also a username.

You can set up an additional password to your account, which can be reset by your email. You don't have to use an email if you do not want to. If you lose access to your email or forget your password, you will be able to reset it via text message if your account is over seven days old and will receive it within a week (in case you recover anything before then).

Telegram uses an open source MTProto encryption protocol that provides complete end-to-end encryption for secret chats. To show off their confidence in the protocol the company behind Telegram has organized $200,000 and $300,000 challenges to break the encryption. So far there have been no winners.

You can write messages to yourself. You can write some notes, add links, and see everything across all your devices.

Even though encryption used for cloud-based storage (e.g. Gmail, Facebook, iCloud) may not be as secure as end-to-end encryption or zero-knowledge storage, Telegram does the most that it can by holding keys to chats in different jurisdictions, requiring intergovernmental cooperation to obtain the keys. This is aside from whatever other security measures have been taken, of course.

There are native desktop, mobile and web client apps, that are optimized for speed and are light on memory usage.

Client apps are open source, making whole service more trustworthy.

Unlimited number of files can be stored forever on the cloud. You can upload files up to 1.5 GB each.

You can post voice and video messages if you are too lazy to write text messages.

This Discord-like feature adds to the interactivity of the application.

You can pin messages to the top of groups or supergroups so members will see them when opening the group.

Messages in individual chats can be set to self destruct on a timer. They will disappear after the timer expires.
Messages in all new chats can be set to self-destruct with a global auto-delete timer in Settings > Privacy and Security > Auto-Delete Messages.

Unfortunately, on the desktop videos don't play, but images are viewable without visiting popular websites like imgur and Instagram.

You can play YouTube videos and others within the app, so you don't need to embed code or anything.

With inline bots, such as @gif, @pic/bing, @vid/YouTube, etc, you can look things up without leaving the client or chat that you're in. Simply type the name and some keywords and wait for the results to load.

You can ping people to get their attention by @mentioning them.

The desktop app has a built in setting to scale the UI of the app up to 200% which allows for those with 4k monitors/screens to use the app without scaling issues.

Uses the latest GPL audio codecs, such as Opus, an adaptative high-quality codec that supersedes AAC at any bitrate.

Although it's volunteer based, but still pretty top-notch if available, which it tends to be.

Topics are now available in groups of 100+ members and have a sleek two-column layout and new buttons to quickly navigate.

A default topic called General is now in every topic group, holding the group’s service messages and previous message history.

On SimilarWeb you can see that Telegram is on the top 15 among all communication apps.