Update README.md

Author: flanglet

README.md

@@ -43,6 +43,30 @@ Use at your own risk. Always keep a copy of your original files.
        src="https://img.shields.io/coverity/scan/16859.svg"/>
 </a>
 
+## Why Kanzi
+
+There are many excellent, open-source lossless data compressors available already.
+
+If gzip is starting to show its age, zstd and brotli are open-source, standardized and used
+daily by millions of people. Zstd is incredibly fast and probably the best choice in many cases.
+There are a few scenarios where Kanzi could be a better choice:
+
+- gzip, lzma, brotli, zstd are all LZ based. It means that they can reach certain compression
+ratios only. Kanzi also makes use of BWT and CM which can compress beyond what LZ can do.
+
+- These LZ based compressors are well suited for software distribution (one compression / many decompressions)
+due to their fast decompression (but low compression speed at high compression ratios). 
+There are other scenarios where compression speed is critical: when data is generated before being compressed and consumed
+(one compression / one decompression) or during backups (many compressions / one decompression).
+
+- Kanzi has built-in data specific transforms (multimedia, utf, text, dna, ...) that can be chosen and combined 
+at compression time to better compress all kinds of data.
+
+- Kanzi can take advantage of the multiple cores of a modern CPU to improve performance
+
+- It is easy to implement a new transform or entropy codec to either test an idea or improve
+compression ratio on speficic kinds of data.
+
 
 ## Benchmarks
 
@@ -54,7 +78,7 @@ clang++ 14.0.0-1ubuntu1.1
 
 Ubuntu 22.04.3 LTS
 
-Kanzi version 2.2 C++ implementation. Default block size.
+Kanzi version 2.2 C++ implementation.
 
 On this machine kanzi can use up to 16 threads depending on compression level
 (the default block size at level 9 is 32MB, severly limiting the number of threads