Tools and taxonomical aids may be different for the study of plants and animals. Herbarium and Botanical garden may be used as tools for the study of plant taxonomy. In the case of animal studies, the classical tools are Museum, Taxonomical Keys and Zoological and Marine parks.
The important components of the taxonomical tools are field visits, survey, identification, classification, preservation and documentation. Many tools are being used for taxonomical studies, amongst them some of the important tools are discussed below:
The classical taxonomical tools:
Taxonomical Keys: Keys are based on comparative analysis of the similarities and dissimilarities of organisms. There are separate keys for different taxonomic categories.
Museum: Biological museums have collection of preserved plants and animals for study and ready reference. Specimens of both extinct and living organisms can be studied.
Zoological parks: These are places where wild animals are kept in protected environments under human care which enables us to study their food habits and behaviour.
Marine parks: Marine organisms are maintained in protected enviroments. Printed taxonomical tools consist of identification cards, description, field guides and manuals.
Molecular taxonomical tools:
Technological advancement has helped to evolve molecular taxonomical tools from classical tools to molecular tools. The accuracy and authenticity is more significant in the molecular tools. The following methods are being used for taxonomical classification.
Molecular techniques and approaches such as DNA barcoding (short genetic marker ill an organism's DNA to identify it as belonging to a particular species), DNA hybridization (measures the degree of genetic similarity between pools of DNA sequences), DNA fingerprinting (to identify an individual from a sample of DNA by looking at unique patterns in their DNA), Restriction Fragment Length Polymorphisms (RFLP) analysis (difference in homologous DNA sequences that can be detected by the presence of fragments of different lengths after digestion of the DNA samples), and Polymerase Chain Reaction (PCR) sequencing ( to amplify a specific gene, or portion of gene,) are used as taxonomical tools.
Automated species Identification tools:
It consists of Cyber tools. eg. DAISY, ALIS, ABIS, SPIDA, Draw wing, etc.

Neo taxonomical tools: This is based on Electron Microscopy images to study the molecular structures of cell organelles.
Ethology of taxonomical tools: Based on the behaviour of the organisms it can be classified. For example sound of birds, bioluminescence, etc
e-Taxonomic resources: iNOTAXA is an electronic resource for digital images and description about the species which was developed by Natural History Museum, London. INOTAXA means Integrated Open TAXonomic Access.

(i) The scientific name should be italicized in printed form and if handwritten, it should be underlined separately.
(ii) The generic name's (Genus) first alphabet should be in uppercase.
(iii) The specific name, (species) should be in lowercase.
(iv) The scientific names of any two organisms are not similar.
(v) The name or abbreviated name of the scientist who first publishes the scientific name mal be written after the species name along with the year of publication. ego Lion-Felis leo Linn., 1758 or Felis leo L., 1758.
(vi) If the species name is framed after any person's name the name of the species shall end with 'i', 'ii' or 'ae'. eg. A new species of a ground-dwelling lizard (Cyrtodactylus) has been discovered and named after scientist Varad Giri, Cyrtodactylus varadgirii.

(i) Definition: The system emphasizes the separation of prokaryotes into two domains, Bacteria and Archaea and 3^rd Eukarya.
(ii) Carl woese (1977) divided Domains into three types. They are
a. Domain Archaea
b. Domain Bacteria and
c. Domain Eukarya
a) Domain Archaea:
Eg: Single celled organisms (prokaryotes)
(i) They live under extreme climatic conditions
(ii) As they have the ability to grow under extreme conditions like volcano vents, hot springs and polar ice caps, the prokaryotes are called as extremophiles
(iii) Chemosynthetic bacteria can synthesize food by the oxidation of inorganics like hydrogen sulphide (H₂S)
(iv) Methane producing organisms are methanogens
(v) Organisms living in salty environment are halophiles
(vi) Organisms live under higher temperatures are thermoacidophiles.
b) Domain Bacteria:
(i) Members are prokaryotes like bacteria
(ii) Cells have no definite true nucleus
(iii) DNA is large, circular, coiled, doubled stranded and naked
(iv) Histones are absent
(v) No membrane bound organelles
(vi) Sub-organelles like 70s type of ribosomes are membranous
(vii) Cell wall is made up of peptidoglycans
(viii) Many bacteria are decomposers (eat on dead decaying organisms)
(ix) Some are photosynthetic and pathogenic
(x) The beneficial probiotic and harmful pathogenic bacteria are diversely populated
(xi) Blue-green algae (prokaryotic plants) like cyanobacteria are photosynthetic they release O₂
(xii) Such bacteria balance atmospheric O₂ level and these were previously anaerobic and become aerobic during the advancement of changes of geographical periods.
c) Domain Eukarya:
(i) All animals belong to Eukarya
(ii) True nucleus and membrane bound organelles and sub-organelles are found-
(iii) DNA in the nucleus is arranged as a linear chromosome
(iv) Histones proteins are present
(v) Ribosomes are of 80s type but 70s type of ribosomes are found in chloroplasts and mitochondria (like in prokaryotes)
(vi) Animals in this domain are classified into Protista, Fungi, Plantae and Animalia

Rules of Nomenclature:
1. The scientific name should be italicized in printed form and if handwritten, it should be underlined separately.
2. The generic name's (Genus) first alphabet should be in uppercase.
3. The specific name (species) should be in lowercase.
4. The scientific names of any two organisms are not similar.
5. The name or abbreviated name of the scientist who first publishes the scientific name may be written after the species name along with the year of publication. Eg: Lion-Felis leo Linn., 1758 or Felis leo L., 1758.
6. If the species name is framed after any person's name the name of the species shall end with i, ii or ae.
7. Eg: A new species of a ground-dwelling lizard (Cyrtodactylus) has been discovered and named after Scientist Varad Giri, Cyrtodactylus varadgiri.