Zip bomb, decompression bomb or the zip of death is a malicious archive file designed to crash or render the program or system reading it.
Consider a very simple compression algorithm that counts the consecutive numbers of 1s and 0s and replace them with the number followed by the bit.
For example: 111100111 is compressed to 412031 (four ones, two zeros and three ones).
You can try this on your own computer. Fill a text file with a massive number of only one character (a file full of ‘0’s), the file size will be in gigabytes but when compressed will become only a few kilobytes.