What is a clustal W alignment?

Clustal W is a widely used bioinformatics tool for multiple sequence alignment, which aligns three or more sequences of DNA, RNA, or protein to identify similarities and differences. It uses a progressive alignment approach, where it first creates a guide tree based on pairwise sequence distances and then aligns sequences in a stepwise manner, refining the alignment as it progresses. Clustal W also incorporates a scoring system to assess the quality of alignments, making it useful for phylogenetic analysis and functional annotation. Its user-friendly interface and ability to handle large datasets have made it a standard tool in molecular Biology.