Compressed Complete Call Graphs (cCCGs) are a newly developed memory data structure for event based program traces. The most important advantage over linear lists or arrays traditionally used is the ability to apply lossy or lossless data compression. The compression scheme is completely transparent with respect to read access, decompression is not required. This approach is a new way to cope with todays challenges when analyzing enormous amounts of trace data. The article focuses on CCG construction and compression, querying and evaluation are briefly covered.