Why Files Become Bigger in Emails - Computerphile

TL;DR

Learn about the limitations of email in sending non-text files and how base64 encoding is used to overcome these limitations.

Transcript

i thought we could revisit the topic of email i know tom rodden way back at the start of computer file did a video overview of how email worked but i want to focus in on one bit which i find quite interesting because i'm that sort of strange type of character and that is how do we transmit things that aren't text through email i mean emails written... Read More

Key Insights

• 🥺 Email was designed to send only ASCII text, which led to limitations in sending non-text files.
• 🫥 The specifications for email restrict the use of non-text characters and have limitations on line length.
• 💌 Base64 encoding converts binary files into text using a lookup table, enabling them to be sent over email.
• 💌 Base64 encoding has become the standard for transmitting binary files in email due to its compatibility and reliability.
• ❓ Other encoding systems, like ASCII 85, have been developed but haven't been as widely adopted.
• 📁 Base64 encoding increases the size of the file being sent, but it allows for the inclusion of non-text files in email transmissions.
• 💌 MIME (Multipurpose Internet Mail Extensions) is another standard that helps in encoding and describing different types of files within an email.

Questions & Answers

Q: How was email originally designed for sending text files?

Email was initially created in the 70s for sending small amounts of ASCII text between two users on a Unix system.

Q: What are the limitations of email in sending non-text files?

Email has a 990-character limit per line and only allows ASCII codes between 1 and 127. Non-text characters, like pictures or audio files, cannot be directly sent.

Q: How does base64 encoding solve the problem of sending non-text files?

Base64 encoding converts binary files into a series of characters using a lookup table. This enables non-text files to be encoded and transmitted as text in email.

Q: Are there alternative encoding systems to base64 for sending binary files?

Yes, other encoding systems like ASCII 85 have been used. However, base64 has become the standard due to its compatibility and widespread adoption.

Summary & Key Takeaways

• Email was originally designed for sending small amounts of ASCII text, but now we send various files like pictures, music, and programs.

• The specifications for email restrict the use of non-text characters and have a limit of 990 characters per line.

• Base64 encoding is used to convert binary files into a series of characters that can be sent over email.