What is e value in fasta?

In a FASTA format, the "e-value" (expectation value) is a statistical measure used in bioinformatics to indicate the number of times a given match or alignment would be expected to occur by chance in a database search. A lower e-value signifies a more significant alignment, suggesting that the observed similarity is less likely to be due to random chance. It is commonly used in tools like BLAST to help assess the quality and relevance of sequence alignments.