Measures for community richness within an environment or variation between different environments

Assembly
Aligning and merging short fragments of sequenced DNA in order to reconstruct the original genome.

Coverage depth
Average number of times a base of a genome is sequenced.

Contiguous fragments of DNA sequence from an incomplete draft genome.

GC content
The GC content of a DNA sequence is the percentage of nucleotides that are either G or C.

Giga base pairs (Gb)

Size of a metagenomics sample in numbers of base pairs

Horizontal gene transfer (HGT)
Exchange or absorption of genetic material independent of reproduction

Environmental gene tags (EGTs)
Short DNA sequences that characterize microbial environments.

Collection of biological DNA fragments prepared for sequencing

Identifying the complete set of transcripts (RNA-seq) from microbial environments

profiling of community-wide protein abundances

Multilocus sequence typing (MLST)
Technique to detect variability of housekeeping genes for identifying bacterial strains

Operational taxonomic units (OTU)

Sequence based species cluster defined by 16S gene sequence similarity

Orthologous genes
Functional identical genes in different species that evolved from a common ancestral gene